diff --git a/CHANGES.md b/CHANGES.md
index 8ab005b94f..bbc7e0b5a2 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -18,6 +18,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 * Bump default `ktfmt` version to latest `0.59` -> `0.61`. ([2804](https://github.com/diffplug/spotless/pull/2804))
 * Bump default `ktlint` version to latest `1.7.1` -> `1.8.0`. ([2763](https://github.com/diffplug/spotless/pull/2763))
 * Bump default `gherkin-utils` version to latest `9.2.0` -> `10.0.0`. ([#2619](https://github.com/diffplug/spotless/pull/2619))
+* Bump default `jackson` version to latest `2.20.1` -> `2.21.0`. ([#2819](https://github.com/diffplug/spotless/pull/2819))
 
 ## [4.1.0] - 2025-11-18
 ### Changes
diff --git a/lib/build.gradle b/lib/build.gradle
index 294f52d55f..046c4c17e2 100644
--- a/lib/build.gradle
+++ b/lib/build.gradle
@@ -97,7 +97,7 @@ dependencies {
 	// gson
 	gsonCompileOnly 'com.google.code.gson:gson:2.13.2'
 	// jackson
-	String VER_JACKSON='2.20.1'
+	String VER_JACKSON='2.21.0'
 	jacksonCompileOnly "com.fasterxml.jackson.core:jackson-databind:$VER_JACKSON"
 	jacksonCompileOnly "com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:$VER_JACKSON"
 	// ktfmt
diff --git a/lib/src/main/java/com/diffplug/spotless/json/JacksonJsonStep.java b/lib/src/main/java/com/diffplug/spotless/json/JacksonJsonStep.java
index 3b8ef48026..6cff411c77 100644
--- a/lib/src/main/java/com/diffplug/spotless/json/JacksonJsonStep.java
+++ b/lib/src/main/java/com/diffplug/spotless/json/JacksonJsonStep.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2021-2025 DiffPlug
+ * Copyright 2021-2026 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,7 +34,7 @@ public final class JacksonJsonStep implements Serializable {
 	@Serial
 	private static final long serialVersionUID = 1L;
 	private static final String MAVEN_COORDINATE = "com.fasterxml.jackson.core:jackson-databind:";
-	private static final String DEFAULT_VERSION = "2.20.1";
+	private static final String DEFAULT_VERSION = "2.21.0";
 	public static final String NAME = "jacksonJson";
 
 	private final JarState.Promised jarState;
diff --git a/plugin-gradle/CHANGES.md b/plugin-gradle/CHANGES.md
index 7dd1fce9d3..9388773b35 100644
--- a/plugin-gradle/CHANGES.md
+++ b/plugin-gradle/CHANGES.md
@@ -12,6 +12,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 * Bump default `ktfmt` version to latest `0.59` -> `0.61`. ([2804](https://github.com/diffplug/spotless/pull/2804))
 * Bump default `ktlint` version to latest `1.7.1` -> `1.8.0`. ([2763](https://github.com/diffplug/spotless/pull/2763))
 * Bump default `gherkin-utils` version to latest `9.2.0` -> `10.0.0`. ([#2619](https://github.com/diffplug/spotless/pull/2619))
+* Bump default `jackson` version to latest `2.20.1` -> `2.21.0`. ([#2819](https://github.com/diffplug/spotless/pull/2819))
 
 ## [8.1.0] - 2025-11-18
 ### Changes
diff --git a/plugin-maven/CHANGES.md b/plugin-maven/CHANGES.md
index 5f99a175a1..54684e9a54 100644
--- a/plugin-maven/CHANGES.md
+++ b/plugin-maven/CHANGES.md
@@ -13,6 +13,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 * Bump default `ktfmt` version to latest `0.59` -> `0.61`. ([2804](https://github.com/diffplug/spotless/pull/2804))
 * Bump default `ktlint` version to latest `1.7.1` -> `1.8.0`. ([2763](https://github.com/diffplug/spotless/pull/2763))
 * Bump default `gherkin-utils` version to latest `9.2.0` -> `10.0.0`. ([#2619](https://github.com/diffplug/spotless/pull/2619))
+* Bump default `jackson` version to latest `2.20.1` -> `2.21.0`. ([#2819](https://github.com/diffplug/spotless/pull/2819))
 
 ## [3.1.0] - 2025-11-18
 ### Changes