diff --git a/actix-http/CHANGES.md b/actix-http/CHANGES.md
index c45a179dc..dc5ff4a85 100644
--- a/actix-http/CHANGES.md
+++ b/actix-http/CHANGES.md
@@ -1,6 +1,10 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+### Fixed
+- Encode correctly camel case header with n+2 hyphens [#2683]
+
+[#2683]: https://github.com/actix/actix-web/issues/2683
 
 
 ## 3.0.1 - 2022-03-04
@@ -750,10 +754,10 @@
 - Remove `ResponseError` impl for `actix::actors::resolver::ResolverError`
   due to deprecate of resolver actor. [#1813]
 - Remove `ConnectError::SslHandshakeError` and re-export of `HandshakeError`.
-  due to the removal of this type from `tokio-openssl` crate. openssl handshake 
+  due to the removal of this type from `tokio-openssl` crate. openssl handshake
   error would return as `ConnectError::SslError`. [#1813]
 - Remove `actix-threadpool` dependency. Use `actix_rt::task::spawn_blocking`.
-  Due to this change `actix_threadpool::BlockingError` type is moved into 
+  Due to this change `actix_threadpool::BlockingError` type is moved into
   `actix_http::error` module. [#1878]
 
 [#1813]: https://github.com/actix/actix-web/pull/1813
diff --git a/actix-http/src/h1/encoder.rs b/actix-http/src/h1/encoder.rs
index ba98f4641..21cfd75c4 100644
--- a/actix-http/src/h1/encoder.rs
+++ b/actix-http/src/h1/encoder.rs
@@ -517,6 +517,7 @@ unsafe fn write_camel_case(value: &[u8], buf: *mut u8, len: usize) {
             if let Some(c @ b'a'..=b'z') = iter.next() {
                 buffer[index] = c & 0b1101_1111;
             }
+            index += 1;
         }
 
         index += 1;
@@ -528,7 +529,7 @@ mod tests {
     use std::rc::Rc;
 
     use bytes::Bytes;
-    use http::header::AUTHORIZATION;
+    use http::header::{AUTHORIZATION, UPGRADE_INSECURE_REQUESTS};
 
     use super::*;
     use crate::{
@@ -559,6 +560,9 @@ mod tests {
         head.headers
             .insert(CONTENT_TYPE, HeaderValue::from_static("plain/text"));
 
+        head.headers
+            .insert(UPGRADE_INSECURE_REQUESTS, HeaderValue::from_static("1"));
+
         let mut head = RequestHeadType::Owned(head);
 
         let _ = head.encode_headers(
@@ -574,6 +578,7 @@ mod tests {
         assert!(data.contains("Connection: close\r\n"));
         assert!(data.contains("Content-Type: plain/text\r\n"));
         assert!(data.contains("Date: date\r\n"));
+        assert!(data.contains("Upgrade-Insecure-Requests: 1\r\n"));
 
         let _ = head.encode_headers(
             &mut bytes,