diff --git a/crates/fff-c/src/lib.rs b/crates/fff-c/src/lib.rs
index 0e0d0c91..d6c5cc3e 100644
--- a/crates/fff-c/src/lib.rs
+++ b/crates/fff-c/src/lib.rs
@@ -736,7 +736,11 @@ pub unsafe extern "C" fn fff_live_grep(
     let options = fff::GrepSearchOptions {
         max_file_size: default_u64(max_file_size, 10 * 1024 * 1024),
         max_matches_per_file: max_matches_per_file as usize,
-        smart_case,
+        case_mode: Some(if smart_case {
+            fff::CaseMode::Smart
+        } else {
+            fff::CaseMode::Sensitive
+        }),
         file_offset: file_offset as usize,
         page_limit: default_u32(page_limit, 50) as usize,
         mode: grep_mode_from_u8(mode),
@@ -746,6 +750,7 @@ pub unsafe extern "C" fn fff_live_grep(
         classify_definitions,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
 
     let result = picker.grep(&parsed, &options);
@@ -839,7 +844,11 @@ pub unsafe extern "C" fn fff_multi_grep(
     let options = fff::GrepSearchOptions {
         max_file_size: default_u64(max_file_size, 10 * 1024 * 1024),
         max_matches_per_file: max_matches_per_file as usize,
-        smart_case,
+        case_mode: Some(if smart_case {
+            fff::CaseMode::Smart
+        } else {
+            fff::CaseMode::Sensitive
+        }),
         file_offset: file_offset as usize,
         page_limit: default_u32(page_limit, 50) as usize,
         mode: fff::GrepMode::PlainText, // ignored by multi_grep_search
@@ -849,6 +858,7 @@ pub unsafe extern "C" fn fff_multi_grep(
         classify_definitions,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
 
     let result = picker.multi_grep(&patterns, constraint_refs, &options);
diff --git a/crates/fff-core/src/grep.rs b/crates/fff-core/src/grep.rs
index 5c73fa5b..2c857fe7 100644
--- a/crates/fff-core/src/grep.rs
+++ b/crates/fff-core/src/grep.rs
@@ -228,6 +228,14 @@ fn replace_unescaped_newline_escapes(text: &str) -> String {
     String::from_utf8(result).unwrap_or_else(|_| text.to_string())
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum CaseMode {
+    #[default]
+    Smart,
+    Sensitive,
+    Insensitive,
+}
+
 /// Controls how the grep pattern is interpreted.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
 pub enum GrepMode {
@@ -334,7 +342,10 @@ pub use crate::constants::MAX_FFFILE_SIZE;
 pub struct GrepSearchOptions {
     pub max_file_size: u64,
     pub max_matches_per_file: usize,
+    #[deprecated(note = "use `case_mode` instead")]
     pub smart_case: bool,
+    /// When `Some`, overrides `smart_case`.
+    pub case_mode: Option<CaseMode>,
     /// File-based pagination offset: index into the sorted/filtered file list
     /// to start searching from. Pass 0 for the first page, then use
     /// `GrepResult::next_file_offset` for subsequent pages.
@@ -364,12 +375,25 @@ pub struct GrepSearchOptions {
     pub abort_signal: Option<Arc<AtomicBool>>,
 }
 
+impl GrepSearchOptions {
+    fn effective_case_mode(&self) -> CaseMode {
+        #[allow(deprecated)]
+        match self.case_mode {
+            Some(m) => m,
+            None if self.smart_case => CaseMode::Smart,
+            None => CaseMode::Sensitive,
+        }
+    }
+}
+
 impl Default for GrepSearchOptions {
     fn default() -> Self {
+        #[allow(deprecated)]
         Self {
             max_file_size: MAX_FFFILE_SIZE,
             max_matches_per_file: 200,
             smart_case: true,
+            case_mode: None,
             file_offset: 0,
             page_limit: 50,
             mode: GrepMode::default(),
@@ -1045,11 +1069,10 @@ pub(crate) fn multi_grep_search<'a>(
         };
     }
 
-    // Smart case: case-insensitive when all patterns are lowercase
-    let case_insensitive = if options.smart_case {
-        !patterns.iter().any(|p| p.chars().any(|c| c.is_uppercase()))
-    } else {
-        false
+    let case_insensitive = match options.effective_case_mode() {
+        CaseMode::Smart => !patterns.iter().any(|p| p.chars().any(|c| c.is_uppercase())),
+        CaseMode::Insensitive => true,
+        CaseMode::Sensitive => false,
     };
 
     let ac = aho_corasick::AhoCorasickBuilder::new()
@@ -1117,7 +1140,7 @@ const fn is_utf8_char_boundary(b: u8) -> bool {
 /// - The input is passed directly to the regex engine without escaping
 /// - Smart case still applies
 /// - Returns `None` for invalid regex patterns — the caller falls back to literal mode
-fn build_regex(pattern: &str, smart_case: bool) -> Result<regex::bytes::Regex, String> {
+fn build_regex(pattern: &str, case_mode: CaseMode) -> Result<regex::bytes::Regex, String> {
     if pattern.is_empty() {
         return Err("empty pattern".to_string());
     }
@@ -1128,10 +1151,10 @@ fn build_regex(pattern: &str, smart_case: bool) -> Result<regex::bytes::Regex, S
         pattern.to_string()
     };
 
-    let case_insensitive = if smart_case {
-        !pattern.chars().any(|c| c.is_uppercase())
-    } else {
-        false
+    let case_insensitive = match case_mode {
+        CaseMode::Smart => !pattern.chars().any(|c| c.is_uppercase()),
+        CaseMode::Insensitive => true,
+        CaseMode::Sensitive => false,
     };
 
     regex::bytes::RegexBuilder::new(&regex_pattern)
@@ -1995,10 +2018,10 @@ pub(crate) fn grep_search<'a>(
         };
     }
 
-    let case_insensitive = if options.smart_case {
-        !grep_text.chars().any(|c| c.is_uppercase())
-    } else {
-        false
+    let case_insensitive = match options.effective_case_mode() {
+        CaseMode::Smart => !grep_text.chars().any(|c| c.is_uppercase()),
+        CaseMode::Insensitive => true,
+        CaseMode::Sensitive => false,
     };
 
     let mut regex_fallback_error: Option<String> = None;
@@ -2089,7 +2112,7 @@ pub(crate) fn grep_search<'a>(
                 overflow_arena,
             );
         }
-        GrepMode::Regex => build_regex(&grep_text, options.smart_case)
+        GrepMode::Regex => build_regex(&grep_text, options.effective_case_mode())
             .inspect_err(|err| {
                 tracing::warn!("Regex compilation failed for {}. Error {}", grep_text, err);
 
@@ -2444,7 +2467,7 @@ mod tests {
         let options = super::GrepSearchOptions {
             max_file_size: MAX_FFFILE_SIZE,
             max_matches_per_file: 0,
-            smart_case: true,
+            case_mode: Some(super::CaseMode::Smart),
             file_offset: 0,
             page_limit: 100,
             mode: super::GrepMode::PlainText,
@@ -2454,6 +2477,7 @@ mod tests {
             classify_definitions: false,
             trim_whitespace: false,
             abort_signal: None,
+            ..Default::default()
         };
         let no_cancel = AtomicBool::new(false);
 
@@ -2628,7 +2652,7 @@ mod tests {
         let options = super::GrepSearchOptions {
             max_file_size: MAX_FFFILE_SIZE,
             max_matches_per_file: 0,
-            smart_case: true,
+            case_mode: Some(super::CaseMode::Smart),
             file_offset: 0,
             page_limit: 100,
             mode: super::GrepMode::PlainText,
@@ -2638,6 +2662,7 @@ mod tests {
             classify_definitions: false,
             trim_whitespace: false,
             abort_signal: Some(std::sync::Arc::new(AtomicBool::new(false))),
+            ..Default::default()
         };
         let result = picker.grep(&query, &options);
 
diff --git a/crates/fff-core/tests/bigram_overlay_coherence_test.rs b/crates/fff-core/tests/bigram_overlay_coherence_test.rs
index 6cee64e4..7369168d 100644
--- a/crates/fff-core/tests/bigram_overlay_coherence_test.rs
+++ b/crates/fff-core/tests/bigram_overlay_coherence_test.rs
@@ -1309,7 +1309,7 @@ fn grep_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::PlainText,
@@ -1319,6 +1319,7 @@ fn grep_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -1653,4 +1654,4 @@ fn bigram_overlay_coherence_fuzzy_grep_finds_overflow_files() {
     }
 
     stop_picker(&shared_picker);
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/bigram_overlay_integration.rs b/crates/fff-core/tests/bigram_overlay_integration.rs
index c663acf8..8d5cbedb 100644
--- a/crates/fff-core/tests/bigram_overlay_integration.rs
+++ b/crates/fff-core/tests/bigram_overlay_integration.rs
@@ -368,7 +368,7 @@ fn grep_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::PlainText,
@@ -378,6 +378,7 @@ fn grep_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -407,4 +408,4 @@ fn wait_for_bigram(shared_picker: &SharedFilePicker) {
             "Timed out waiting for bigram build"
         );
     }
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/fuzz_file_operations.rs b/crates/fff-core/tests/fuzz_file_operations.rs
index e39a6906..24374d8e 100644
--- a/crates/fff-core/tests/fuzz_file_operations.rs
+++ b/crates/fff-core/tests/fuzz_file_operations.rs
@@ -626,7 +626,7 @@ fn grep_plain_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::PlainText,
@@ -636,6 +636,7 @@ fn grep_plain_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -857,4 +858,4 @@ fn drop_during_post_scan_does_not_crash() {
          The test is not exercising the race. ({caught_active}/10)"
     );
     eprintln!("Caught post-scan active in {caught_active}/10 rounds");
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/fuzz_git_watcher_stress.rs b/crates/fff-core/tests/fuzz_git_watcher_stress.rs
index f7ca1e80..74ed7306 100644
--- a/crates/fff-core/tests/fuzz_git_watcher_stress.rs
+++ b/crates/fff-core/tests/fuzz_git_watcher_stress.rs
@@ -891,7 +891,7 @@ fn grep_plain_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
     let opts = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::PlainText,
@@ -901,6 +901,7 @@ fn grep_plain_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     let result = picker.grep(&parsed, &opts);
     // `GrepResult::files` is the already-deduplicated list of files that
@@ -928,7 +929,7 @@ fn grep_fuzzy_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
     let opts = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::Fuzzy,
@@ -938,6 +939,7 @@ fn grep_fuzzy_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     let result = picker.grep(&parsed, &opts);
     result
@@ -960,7 +962,7 @@ fn grep_regex_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
     let opts = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::Regex,
@@ -970,6 +972,7 @@ fn grep_regex_matches(shared: &SharedFilePicker, query: &str) -> Vec<String> {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     let result = picker.grep(&parsed, &opts);
     result
@@ -1607,4 +1610,4 @@ fn expect_file_status(
         }
         std::thread::sleep(CONVERGE_POLL);
     }
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/fuzz_real_repos.rs b/crates/fff-core/tests/fuzz_real_repos.rs
index f83a0f52..81db683b 100644
--- a/crates/fff-core/tests/fuzz_real_repos.rs
+++ b/crates/fff-core/tests/fuzz_real_repos.rs
@@ -226,7 +226,7 @@ fn grep_opts(mode: GrepMode) -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode,
@@ -236,6 +236,7 @@ fn grep_opts(mode: GrepMode) -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -737,4 +738,4 @@ proptest! {
     fn fuzz_real_repos_proptest(ops in ops_strategy()) {
         run_scenario(&ops);
     }
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/grep_integration.rs b/crates/fff-core/tests/grep_integration.rs
index 2765de3c..71e0a5f8 100644
--- a/crates/fff-core/tests/grep_integration.rs
+++ b/crates/fff-core/tests/grep_integration.rs
@@ -31,7 +31,7 @@ fn plain_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::PlainText,
@@ -41,6 +41,7 @@ fn plain_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -49,7 +50,7 @@ fn regex_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::Regex,
@@ -59,6 +60,7 @@ fn regex_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -67,7 +69,7 @@ fn fuzzy_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::Fuzzy,
@@ -77,6 +79,7 @@ fn fuzzy_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -1834,4 +1837,4 @@ fn plain_text_smart_case_finds_uppercase_content_with_lowercase_query() {
         1,
         "lowercase query should case-insensitively match 'VFIO-KVM'"
     );
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/new_directory_watcher_test.rs b/crates/fff-core/tests/new_directory_watcher_test.rs
index 9cb9fc11..095a510f 100644
--- a/crates/fff-core/tests/new_directory_watcher_test.rs
+++ b/crates/fff-core/tests/new_directory_watcher_test.rs
@@ -132,7 +132,7 @@ fn grep_plain_count(picker: &FilePicker, query: &str) -> usize {
     let opts = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 500,
         mode: GrepMode::PlainText,
@@ -142,6 +142,7 @@ fn grep_plain_count(picker: &FilePicker, query: &str) -> usize {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     picker.grep(&parsed, &opts).matches.len()
 }
@@ -536,4 +537,4 @@ fn gitignored_new_directory_excluded() {
         let grep_count = grep_plain_count(picker, "IGNORED_BUILD_TOKEN");
         assert_eq!(grep_count, 0, "Gitignored content should NOT be grepable");
     }
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/path_separator_constraint_test.rs b/crates/fff-core/tests/path_separator_constraint_test.rs
index 9519ef83..7b7110c9 100644
--- a/crates/fff-core/tests/path_separator_constraint_test.rs
+++ b/crates/fff-core/tests/path_separator_constraint_test.rs
@@ -36,7 +36,7 @@ fn plain_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::PlainText,
@@ -46,6 +46,7 @@ fn plain_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -245,4 +246,4 @@ fn fuzzy_search_with_glob_constraint_matches_on_windows_paths() {
         results.iter().any(|p| p.contains("handler.lua")),
         "glob `**/src/**/*.lua` must match services/handler.lua, got {results:?}"
     );
-}
+}
\ No newline at end of file
diff --git a/crates/fff-core/tests/real_binary_fixtures.rs b/crates/fff-core/tests/real_binary_fixtures.rs
index d7f383b6..4b6c8261 100644
--- a/crates/fff-core/tests/real_binary_fixtures.rs
+++ b/crates/fff-core/tests/real_binary_fixtures.rs
@@ -30,7 +30,7 @@ fn plain_opts() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff_search::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 200,
         mode: GrepMode::PlainText,
@@ -40,6 +40,7 @@ fn plain_opts() -> GrepSearchOptions {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
@@ -150,4 +151,4 @@ fn contains_subslice(haystack: &[u8], needle: &[u8]) -> bool {
     haystack
         .windows(needle.len())
         .any(|window| window == needle)
-}
+}
\ No newline at end of file
diff --git a/crates/fff-mcp/src/server.rs b/crates/fff-mcp/src/server.rs
index 0fc6102a..4e9ad7ec 100644
--- a/crates/fff-mcp/src/server.rs
+++ b/crates/fff-mcp/src/server.rs
@@ -10,7 +10,7 @@ use std::sync::{Arc, Mutex};
 
 use crate::cursor::CursorStore;
 use crate::output::{GrepFormatter, OutputMode, file_suffix};
-use fff::grep::{GrepMode, GrepSearchOptions, has_regex_metacharacters};
+use fff::grep::{CaseMode, GrepMode, GrepSearchOptions, has_regex_metacharacters};
 use fff::types::{FileItem, PaginationArgs};
 use fff::{FuzzySearchOptions, QueryParser, SharedFilePicker, SharedFrecency};
 use fff_query_parser::AiGrepConfig;
@@ -66,7 +66,7 @@ fn make_grep_options(
         GrepSearchOptions {
             max_file_size: 10 * 1024 * 1024,
             max_matches_per_file: matches_per_file,
-            smart_case: true,
+            case_mode: Some(CaseMode::Smart),
             file_offset,
             page_limit: 50,
             mode,
@@ -76,6 +76,7 @@ fn make_grep_options(
             classify_definitions: true,
             trim_whitespace: true,
             abort_signal: None,
+            ..Default::default()
         },
         auto_expand,
     )
diff --git a/crates/fff-nvim/benches/fuzzy_search_bench.rs b/crates/fff-nvim/benches/fuzzy_search_bench.rs
index 8a1fcd57..fe12bdc0 100644
--- a/crates/fff-nvim/benches/fuzzy_search_bench.rs
+++ b/crates/fff-nvim/benches/fuzzy_search_bench.rs
@@ -627,7 +627,7 @@ fn bench_grep_search(c: &mut Criterion) {
     let options = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 0,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 100,
         mode: GrepMode::PlainText,
@@ -637,6 +637,7 @@ fn bench_grep_search(c: &mut Criterion) {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
 
     let test_queries = vec![
@@ -672,4 +673,4 @@ criterion_group!(
     bench_grep_search,
 );
 
-criterion_main!(benches);
+criterion_main!(benches);
\ No newline at end of file
diff --git a/crates/fff-nvim/benches/grep_bench.rs b/crates/fff-nvim/benches/grep_bench.rs
index 64939946..225e8a75 100644
--- a/crates/fff-nvim/benches/grep_bench.rs
+++ b/crates/fff-nvim/benches/grep_bench.rs
@@ -110,7 +110,7 @@ fn plain_options() -> GrepSearchOptions {
     GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 50,
         mode: GrepMode::PlainText,
@@ -233,4 +233,4 @@ criterion_group!(
     bench_plain_no_index,
 );
 
-criterion_main!(benches);
+criterion_main!(benches);
\ No newline at end of file
diff --git a/crates/fff-nvim/src/bin/bench_grep_query.rs b/crates/fff-nvim/src/bin/bench_grep_query.rs
index 063d0816..19cf13ff 100644
--- a/crates/fff-nvim/src/bin/bench_grep_query.rs
+++ b/crates/fff-nvim/src/bin/bench_grep_query.rs
@@ -22,7 +22,7 @@ fn run_grep(picker: &FilePicker, query: &str, iters: usize) {
     let options = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: usize::MAX,
         mode: GrepMode::PlainText,
@@ -32,6 +32,7 @@ fn run_grep(picker: &FilePicker, query: &str, iters: usize) {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
 
     let parsed = parse_grep_query(query);
@@ -135,4 +136,4 @@ fn main() {
         query, iters
     );
     run_grep(&picker, query, iters);
-}
+}
\ No newline at end of file
diff --git a/crates/fff-nvim/src/bin/fuzzy_grep_test.rs b/crates/fff-nvim/src/bin/fuzzy_grep_test.rs
index e3bceac8..7fd2cf31 100644
--- a/crates/fff-nvim/src/bin/fuzzy_grep_test.rs
+++ b/crates/fff-nvim/src/bin/fuzzy_grep_test.rs
@@ -27,7 +27,7 @@ fn run_fuzzy_query(picker: &FilePicker, query: &str, label: &str) {
     let options = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 100,
         mode: GrepMode::Fuzzy,
@@ -37,6 +37,7 @@ fn run_fuzzy_query(picker: &FilePicker, query: &str, label: &str) {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
 
     let parsed = parse_grep_query(query);
@@ -180,4 +181,4 @@ fn main() {
     }
 
     eprintln!("=== Done ===");
-}
+}
\ No newline at end of file
diff --git a/crates/fff-nvim/src/bin/grep_profiler.rs b/crates/fff-nvim/src/bin/grep_profiler.rs
index 4c0386b2..487e4a9e 100644
--- a/crates/fff-nvim/src/bin/grep_profiler.rs
+++ b/crates/fff-nvim/src/bin/grep_profiler.rs
@@ -88,7 +88,7 @@ impl<'a> GrepBench<'a> {
             options: GrepSearchOptions {
                 max_file_size: 10 * 1024 * 1024,
                 max_matches_per_file: 200,
-                smart_case: true,
+                case_mode: Some(fff::grep::CaseMode::Smart),
                 file_offset: 0,
                 page_limit: 50,
                 mode,
@@ -98,6 +98,7 @@ impl<'a> GrepBench<'a> {
                 classify_definitions: false,
                 trim_whitespace: false,
                 abort_signal: None,
+                ..Default::default()
             },
         }
     }
@@ -409,7 +410,7 @@ fn main() {
         let opts = GrepSearchOptions {
             max_file_size: 10 * 1024 * 1024,
             max_matches_per_file: 200,
-            smart_case: true,
+            case_mode: Some(fff::grep::CaseMode::Smart),
             file_offset,
             page_limit: 50,
             mode: Default::default(),
@@ -419,6 +420,7 @@ fn main() {
             classify_definitions: false,
             trim_whitespace: false,
             abort_signal: None,
+            ..Default::default()
         };
         let start = Instant::now();
         let result = picker.grep(&parsed, &opts);
@@ -450,4 +452,4 @@ fn main() {
     eprintln!("\nDone. For perf profiling:");
     eprintln!("  perf record -g --call-graph dwarf -F 999 ./target/release/grep_profiler");
     eprintln!("  perf report --no-children");
-}
+}
\ No newline at end of file
diff --git a/crates/fff-nvim/src/bin/grep_vs_rg.rs b/crates/fff-nvim/src/bin/grep_vs_rg.rs
index f202fc1f..9e05a5fe 100644
--- a/crates/fff-nvim/src/bin/grep_vs_rg.rs
+++ b/crates/fff-nvim/src/bin/grep_vs_rg.rs
@@ -162,7 +162,7 @@ fn run_fff_full(picker: &FilePicker, query: &str) -> (usize, Duration) {
     let options = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: usize::MAX,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: usize::MAX,
         mode: Default::default(),
@@ -172,6 +172,7 @@ fn run_fff_full(picker: &FilePicker, query: &str) -> (usize, Duration) {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     let start = Instant::now();
     let result = picker.grep(&parsed, &options);
@@ -185,7 +186,7 @@ fn run_fff_page(picker: &FilePicker, query: &str) -> (usize, Duration) {
     let options = GrepSearchOptions {
         max_file_size: 10 * 1024 * 1024,
         max_matches_per_file: 200,
-        smart_case: true,
+        case_mode: Some(fff::grep::CaseMode::Smart),
         file_offset: 0,
         page_limit: 50,
         mode: Default::default(),
@@ -195,6 +196,7 @@ fn run_fff_page(picker: &FilePicker, query: &str) -> (usize, Duration) {
         classify_definitions: false,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     };
     let start = Instant::now();
     let result = picker.grep(&parsed, &options);
@@ -440,4 +442,4 @@ fn main() {
     eprintln!("  on EVERY invocation (= every keystroke in telescope/fzf-lua).");
     eprintln!("  fff pays this cost once at startup, then searches from warm cached mmaps.");
     eprintln!();
-}
+}
\ No newline at end of file
diff --git a/crates/fff-nvim/src/lib.rs b/crates/fff-nvim/src/lib.rs
index a9f3cb2d..52a71251 100644
--- a/crates/fff-nvim/src/lib.rs
+++ b/crates/fff-nvim/src/lib.rs
@@ -436,6 +436,7 @@ pub fn live_grep(
         grep_mode,
         time_budget_ms,
         trim_whitespace,
+        case_mode,
     ): (
         String,
         Option<usize>,
@@ -446,6 +447,7 @@ pub fn live_grep(
         Option<String>,
         Option<u64>,
         Option<bool>,
+        Option<String>,
     ),
 ) -> LuaResult<LuaValue> {
     let file_picker_guard = FILE_PICKER.read().into_lua_result()?;
@@ -460,10 +462,21 @@ pub fn live_grep(
         _ => fff::GrepMode::PlainText, // "plain" or nil or unknown
     };
 
+    let case_mode = match case_mode.as_deref() {
+        Some("smart") => Some(fff::CaseMode::Smart),
+        Some("sensitive") => Some(fff::CaseMode::Sensitive),
+        Some("insensitive") => Some(fff::CaseMode::Insensitive),
+        _ => Some(if smart_case.unwrap_or(true) {
+            fff::CaseMode::Smart
+        } else {
+            fff::CaseMode::Sensitive
+        }),
+    };
+
     let options = fff::GrepSearchOptions {
         max_file_size: max_file_size.unwrap_or(10 * 1024 * 1024),
         max_matches_per_file: max_matches_per_file.unwrap_or(200),
-        smart_case: smart_case.unwrap_or(true),
+        case_mode,
         file_offset: file_offset.unwrap_or(0),
         page_limit: page_size.unwrap_or(50),
         mode,
@@ -473,6 +486,7 @@ pub fn live_grep(
         classify_definitions: false,
         trim_whitespace: trim_whitespace.unwrap_or(false),
         abort_signal: None,
+        ..Default::default()
     };
 
     let result = picker.grep(&parsed_query, &options);
diff --git a/crates/fff-python/src/finder.rs b/crates/fff-python/src/finder.rs
index e61232fc..78106e65 100644
--- a/crates/fff-python/src/finder.rs
+++ b/crates/fff-python/src/finder.rs
@@ -5,8 +5,8 @@ use fff::file_picker::FilePicker;
 use fff::frecency::FrecencyTracker;
 use fff::query_tracker::QueryTracker;
 use fff::{
-    FFFMode, FilePickerOptions, FuzzySearchOptions, GrepSearchOptions, PaginationArgs, QueryParser,
-    SharedFilePicker, SharedFrecency, SharedQueryTracker,
+    CaseMode, FFFMode, FilePickerOptions, FuzzySearchOptions, GrepSearchOptions, PaginationArgs,
+    QueryParser, SharedFilePicker, SharedFrecency, SharedQueryTracker,
 };
 use pyo3::prelude::*;
 use pyo3::types::PyDict;
@@ -90,7 +90,11 @@ fn grep_options(
     GrepSearchOptions {
         max_file_size: defaulted_u64(max_file_size, defaults.max_file_size),
         max_matches_per_file: max_matches_per_file as usize,
-        smart_case,
+        case_mode: Some(if smart_case {
+            CaseMode::Smart
+        } else {
+            CaseMode::Sensitive
+        }),
         file_offset: cursor_offset,
         page_limit: defaulted_usize(page_limit, defaults.page_limit),
         mode,
@@ -100,6 +104,7 @@ fn grep_options(
         classify_definitions,
         trim_whitespace: false,
         abort_signal: None,
+        ..Default::default()
     }
 }
 
diff --git a/lua/fff/conf.lua b/lua/fff/conf.lua
index dcb53e01..d5c3d968 100644
--- a/lua/fff/conf.lua
+++ b/lua/fff/conf.lua
@@ -56,6 +56,7 @@ local M = {}
 --- @field max_file_size number
 --- @field max_matches_per_file number
 --- @field smart_case boolean
+--- @field case_mode? "smart"|"sensitive"|"insensitive"
 --- @field time_budget_ms number
 --- @field modes string[]
 --- @field trim_whitespace boolean
@@ -414,7 +415,8 @@ local function init()
     grep = {
       max_file_size = 10 * 1024 * 1024, -- Skip files larger than 10MB
       max_matches_per_file = 100, -- Maximum matches per file (set 0 to unlimited)
-      smart_case = true, -- Case-insensitive unless query has uppercase
+      smart_case = true, -- Case-insensitive unless query has uppercase (legacy; prefer case_mode)
+      case_mode = nil, -- Optional: "smart" | "sensitive" | "insensitive". Overrides smart_case when set.
       time_budget_ms = 150, -- Max search time in ms per call (prevents UI freeze, 0 = no limit)
       modes = { 'plain', 'regex', 'fuzzy' }, -- Available grep modes and their cycling order
       trim_whitespace = false, -- Strip leading whitespace from matched lines (useful for cleaner display)
diff --git a/lua/fff/main.lua b/lua/fff/main.lua
index 1418a2d7..59eee551 100644
--- a/lua/fff/main.lua
+++ b/lua/fff/main.lua
@@ -302,6 +302,7 @@ end
 --- @field max_file_size? number Skip files larger than N bytes (default: config.grep.max_file_size).
 --- @field max_matches_per_file? number Cap matches per file, 0 = unlimited (default: config.grep.max_matches_per_file).
 --- @field smart_case? boolean Case-insensitive when query is all lowercase (default: config.grep.smart_case).
+--- @field case_mode? "smart"|"sensitive"|"insensitive" Explicit case mode (default: config.grep.case_mode). Overrides smart_case.
 --- @field page_size? number Max matches returned (default: 50).
 --- @field file_offset? number File-based pagination offset (default: 0).
 --- @field time_budget_ms? number Max wall-clock time, 0 = unlimited (default: config.grep.time_budget_ms).
@@ -348,6 +349,7 @@ function M.content_search(query, opts)
     max_file_size = opts.max_file_size or grep_cfg.max_file_size,
     max_matches_per_file = opts.max_matches_per_file or grep_cfg.max_matches_per_file,
     smart_case = opts.smart_case == nil and grep_cfg.smart_case or opts.smart_case,
+    case_mode = opts.case_mode == nil and grep_cfg.case_mode or opts.case_mode,
     time_budget_ms = opts.time_budget_ms or grep_cfg.time_budget_ms,
     trim_whitespace = opts.trim_whitespace == nil and grep_cfg.trim_whitespace or opts.trim_whitespace,
   }
diff --git a/lua/fff/picker_ui/grep_renderer.lua b/lua/fff/picker_ui/grep_renderer.lua
index ef022afc..db20acc7 100644
--- a/lua/fff/picker_ui/grep_renderer.lua
+++ b/lua/fff/picker_ui/grep_renderer.lua
@@ -40,7 +40,8 @@ function M.search(query, file_offset, page_size, config, grep_mode)
     conf.smart_case,
     grep_mode or 'plain',
     conf.time_budget_ms,
-    conf.trim_whitespace
+    conf.trim_whitespace,
+    conf.case_mode
   )
   return last_result
 end