diff --git a/cli-excel-rs/src/main.rs b/cli-excel-rs/src/main.rs
index 433699d..1cee10e 100644
--- a/cli-excel-rs/src/main.rs
+++ b/cli-excel-rs/src/main.rs
@@ -13,7 +13,8 @@ fn cli() -> Command {
             Command::new("csv")
                 .about("Convert a csv file to xlsx")
                 .arg(arg!(--in <FILE> "csv file to convert"))
-                .arg(arg!(--out <FILE> "xlsx output file name")),
+                .arg(arg!(--out <FILE> "xlsx output file name"))
+                .arg(arg!(--filter "Freeze the top row and add auto-filters")),
         )
 }
 
@@ -25,6 +26,8 @@ fn main() {
             let input = sub_matches.get_one::<String>("in").expect("required");
             let out = sub_matches.get_one::<String>("out").expect("required");
 
+            let apply_filter = sub_matches.get_flag("filter");
+
             let mut f = File::open(input).expect("input csv file not found");
             let mut data: Vec<u8> = Vec::new();
 
@@ -34,6 +37,15 @@ fn main() {
             let mut workbook = WorkBook::new(Cursor::new(output_buffer));
             let mut worksheet = workbook.get_worksheet(String::from("Sheet 1"));
 
+            // Apply filters first if requested
+            if apply_filter {
+                worksheet.freeze_top_row();
+                worksheet.add_auto_filter();
+            }
+
+            // Initialize the sheet before writing any rows
+            worksheet.init_sheet().expect("Failed to initialize worksheet");
+
             let mut reader = bytes_to_csv(data.as_slice());
             let headers = get_headers(&mut reader);
 
diff --git a/crates/excel-rs-xlsx/src/sheet.rs b/crates/excel-rs-xlsx/src/sheet.rs
index 112b5e9..e50afff 100644
--- a/crates/excel-rs-xlsx/src/sheet.rs
+++ b/crates/excel-rs-xlsx/src/sheet.rs
@@ -12,10 +12,12 @@ pub struct Sheet<'a, W: Write + Seek> {
     // pub id: u16,
     // pub is_closed: bool,
     col_num_to_letter: Vec<Vec<u8>>,
-    current_row_num: u32
+    current_row_num: u32,
+    has_auto_filter: bool,
+    sheet_data_started: bool,  // Add this to track if we've started sheetData
+    freeze_top_row: bool,      // Add this to track if we should freeze the top row
 }
 
-
 impl<'a, W: Write + Seek> Sheet<'a, W> {
     pub fn new(name: String, id: u16, writer: &'a mut ZipWriter<W>) -> Self {
         let options = SimpleFileOptions::default()
@@ -27,21 +29,56 @@ impl<'a, W: Write + Seek> Sheet<'a, W> {
             .start_file(format!("xl/worksheets/sheet{}.xml", id), options)
             .ok();
 
-        // Writes Sheet Header
-        writer.write(b"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n<worksheet xmlns=\"http://schemas.openxmlformats.org/spreadsheetml/2006/main\" xmlns:r=\"http://schemas.openxmlformats.org/officeDocument/2006/relationships\">\n<sheetData>\n").ok();
-
+        writer.write(b"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n\
+            <worksheet xmlns=\"http://schemas.openxmlformats.org/spreadsheetml/2006/main\" \
+            xmlns:r=\"http://schemas.openxmlformats.org/officeDocument/2006/relationships\">\n").ok();
 
         Sheet {
             sheet_buf: writer,
-            // id,
             _name: name,
-            // is_closed: false,
             col_num_to_letter: Vec::with_capacity(64),
-            current_row_num: 0
+            current_row_num: 1,
+            has_auto_filter: false,
+            sheet_data_started: false,
+            freeze_top_row: false,
+        }
+    }
+
+    // Public method to set the freeze flag
+    pub fn freeze_top_row(&mut self) {
+        self.freeze_top_row = true;
+    }
+
+    // Private method to write the sheetViews XML
+    fn write_sheet_views(&mut self) -> Result<()> {
+        if self.sheet_data_started {
+            return Ok(());  // Can't write sheetViews after sheetData has started
+        }
+        
+        self.sheet_buf.write(b"<sheetViews>\n\
+            <sheetView tabSelected=\"1\" workbookViewId=\"0\" zoomScale=\"100\">\n\
+            <pane ySplit=\"1\" xSplit=\"0\" topLeftCell=\"A2\" activePane=\"bottomLeft\" state=\"frozen\" />\n\
+            <selection pane=\"topLeft\" />\n\
+            <selection pane=\"bottomLeft\" activeCell=\"A2\" sqref=\"A2\" />\n\
+            </sheetView>\n\
+            </sheetViews>\n")?;
+
+        self.sheet_data_started = true;
+
+        Ok(())
+    }
+
+    // New public method to initialize the sheet
+    pub fn init_sheet(&mut self) -> Result<()> {
+        // Write sheetViews if requested
+        if self.freeze_top_row {
+            self.write_sheet_views()?;
         }
+        // Write sheetData start tag
+        self.sheet_buf.write(b"<sheetData>\n")?;
+        Ok(())
     }
 
-    // TOOD: Use ShortVec over Vec for cell ID
     pub fn write_row(&mut self, data: Vec<&[u8]>) -> Result<()> {
         let mut final_vec = Vec::with_capacity(512 * data.len());
 
@@ -74,9 +111,10 @@ impl<'a, W: Write + Seek> Sheet<'a, W> {
             col += 1;
         }
 
-        final_vec.write(b"</row>")?;
+        final_vec.write(b"</row>\n")?;
 
         self.sheet_buf.write(&final_vec)?;
+        self.current_row_num += 1;
 
         Ok(())
     }
@@ -115,16 +153,40 @@ impl<'a, W: Write + Seek> Sheet<'a, W> {
     }
 
     pub fn close(&mut self) -> Result<()> {
-        self.sheet_buf.write(b"\n</sheetData>\n</worksheet>\n")?;
+        // Close sheetData
+        self.sheet_buf.write(b"</sheetData>\n")?;
+
+        // Write autoFilter if requested
+        if self.has_auto_filter {
+            let num_columns = self.col_num_to_letter.len();
+            if num_columns > 0 {
+                let last_col_letter = self.col_to_letter(num_columns - 1);
+                let auto_filter_range = format!("A1:{}1", String::from_utf8_lossy(last_col_letter));
+                self.sheet_buf.write(format!("<autoFilter ref=\"{}\"/>\n", auto_filter_range).as_bytes())?;
+            }
+        }
+
+        // Close worksheet
+        self.sheet_buf.write(b"</worksheet>")?;
         Ok(())
     }
 
+    pub fn add_auto_filter(&mut self) {
+        self.has_auto_filter = true;
+    }
+
     fn num_to_bytes(&self, n: u32) -> ([u8; 9], usize) {
         // Convert from number to string manually
         let mut row_in_chars_arr: [u8; 9] = [0; 9];
         let mut row = n;
         let mut char_pos = 8;
         let mut digits = 0;
+
+        if row == 0 {
+            row_in_chars_arr[8] = b'0';
+            return (row_in_chars_arr, 1);
+        }
+
         while row > 0 {
             row_in_chars_arr[char_pos] = b'0' + (row % 10) as u8;
             row = row / 10;