diff --git a/Cargo.lock b/Cargo.lock
index 9bb2489c8..02eabe3f1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -859,7 +859,7 @@ dependencies = [
 
 [[package]]
 name = "pkcs1"
-version = "0.4.0-pre.2"
+version = "0.4.0"
 dependencies = [
  "der 0.6.0",
  "hex-literal",
diff --git a/pkcs1/CHANGELOG.md b/pkcs1/CHANGELOG.md
index e042df61d..e607ae727 100644
--- a/pkcs1/CHANGELOG.md
+++ b/pkcs1/CHANGELOG.md
@@ -4,6 +4,16 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.4.0 (2022-05-08)
+### Changed
+- Replace document types with `doc::{Document, SecretDocument}` types ([#571])
+- Bump `der` to v0.6 ([#653])
+- Bump `pkcs8` to v0.9 ([#656])
+
+[#571]: https://github.com/RustCrypto/formats/pull/571
+[#653]: https://github.com/RustCrypto/formats/pull/653
+[#656]: https://github.com/RustCrypto/formats/pull/656
+
 ## 0.3.3 (2022-01-16)
 ### Added
 - Error conversion support to `pkcs8::spki::Error` ([#333])
diff --git a/pkcs1/Cargo.toml b/pkcs1/Cargo.toml
index a11870597..00f641406 100644
--- a/pkcs1/Cargo.toml
+++ b/pkcs1/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "pkcs1"
-version = "0.4.0-pre.2" # Also update html_root_url in lib.rs when bumping this
+version = "0.4.0" # Also update html_root_url in lib.rs when bumping this
 description = """
 Pure Rust implementation of Public-Key Cryptography Standards (PKCS) #1:
 RSA Cryptography Specifications Version 2.2 (RFC 8017)