diff --git a/CHANGES.md b/CHANGES.md
index 125aaa7327..dba135171f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -17,6 +17,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 - `FenceStep.preserveWithin` now forwards lints from nested steps while still suppressing lints inside preserved blocks. ([#2962](https://github.com/diffplug/spotless/pull/2962))
 - Support `ktfmt` 0.63 and use its new builder API for formatting options to better avoid future breaking changes.
 - Parse standard git year output in LicenseHeaderStep. ([#2940](https://github.com/diffplug/spotless/issues/2940))
+- Fix `StringIndexOutOfBoundsException` in scenarios where copyright year is surrounded by whitespace. ([#2973](https://github.com/diffplug/spotless/pull/2973))
 
 ### Changes
 - Bump default `greclipse` version to latest `4.35` -> `4.39`. ([#2924](https://github.com/diffplug/spotless/pull/2924))
diff --git a/lib/src/main/java/com/diffplug/spotless/generic/LicenseHeaderStep.java b/lib/src/main/java/com/diffplug/spotless/generic/LicenseHeaderStep.java
index edb4d73f6f..91ef59a21b 100644
--- a/lib/src/main/java/com/diffplug/spotless/generic/LicenseHeaderStep.java
+++ b/lib/src/main/java/com/diffplug/spotless/generic/LicenseHeaderStep.java
@@ -380,7 +380,7 @@ private String calculateYearBySearching(String content) {
 				String secondYear = null;
 				if (updateYearWithLatest) {
 					secondYear = firstYear.equals(yearToday) ? null : yearToday;
-				} else {
+				} else if (yearMatcher.end() + 1 < content.length()) {
 					String contentWithSecondYear = content.substring(yearMatcher.end() + 1);
 					int endOfLine = contentWithSecondYear.indexOf('\n');
 					if (endOfLine != -1) {
diff --git a/plugin-gradle/CHANGES.md b/plugin-gradle/CHANGES.md
index 03d3f6d8b7..d4387c43e5 100644
--- a/plugin-gradle/CHANGES.md
+++ b/plugin-gradle/CHANGES.md
@@ -11,6 +11,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 - `toggleOffOn` no longer disables lint-only steps such as `forbidWildcardImports`. ([#2962](https://github.com/diffplug/spotless/pull/2962))
 - Prevent build caches from interfering when executing under the `-PspotlessIdeHook` mode. ([#2365](https://github.com/diffplug/spotless/issues/2365))
 - Parse standard git year output in LicenseHeaderStep. ([#2940](https://github.com/diffplug/spotless/issues/2940))
+- Fix `StringIndexOutOfBoundsException` in scenarios where copyright year is surrounded by whitespace. ([#2973](https://github.com/diffplug/spotless/pull/2973))
 
 ### Changes
 - Bump default `greclipse` version to latest `4.35` -> `4.39`. ([#2924](https://github.com/diffplug/spotless/pull/2924))
diff --git a/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/LicenseHeaderTest.java b/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/LicenseHeaderTest.java
index a8ac2dd9cc..c06958cbd5 100644
--- a/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/LicenseHeaderTest.java
+++ b/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/LicenseHeaderTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2025 DiffPlug
+ * Copyright 2016-2026 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -56,13 +56,32 @@ private void assertTransform(String yearBefore, String yearAfter) throws IOExcep
 	private void testSuiteUpdateWithLatest(boolean update) throws IOException {
 		if (update) {
 			assertTransform("2003", "2003-" + NOW);
+			assertTransform("   2003", "2003-" + NOW);
+			assertTransform("2003   ", "2003-" + NOW);
+			assertTransform("   2003   ", "2003-" + NOW);
+
 			assertTransform("2003-2005", "2003-" + NOW);
+			assertTransform("   2003-2005", "2003-" + NOW);
+			assertTransform("2003-2005   ", "2003-" + NOW);
+			assertTransform("   2003-2005   ", "2003-" + NOW);
 		} else {
 			assertUnchanged("2003");
+			assertTransform("   2003", "2003");
+			assertTransform("2003   ", "2003");
+			assertTransform("   2003   ", "2003");
+
 			assertUnchanged("2003-2005");
+			assertTransform("   2003-2005", "2003-2005");
+			assertTransform("2003-2005   ", "2003-2005");
+			assertTransform("   2003-2005   ", "2003-2005");
 		}
 		assertUnchanged(NOW);
+		assertTransform("   " + NOW, NOW);
+		assertTransform(NOW + "   ", NOW);
+		assertTransform("   " + NOW + "   ", NOW);
+
 		assertTransform("", NOW);
+		assertTransform("   ", NOW);
 	}
 
 	@Test
diff --git a/plugin-maven/CHANGES.md b/plugin-maven/CHANGES.md
index e5d7df51e0..45b18fce23 100644
--- a/plugin-maven/CHANGES.md
+++ b/plugin-maven/CHANGES.md
@@ -6,6 +6,8 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ### Fixed
 - Parse standard git year output in LicenseHeaderStep. ([#2940](https://github.com/diffplug/spotless/issues/2940))
 - `<toggleOffOn>` no longer disables lint-only steps such as `<forbidWildcardImports>`. ([#2962](https://github.com/diffplug/spotless/pull/2962))
+- Fix `StringIndexOutOfBoundsException` in scenarios where copyright year is surrounded by whitespace. ([#2973](https://github.com/diffplug/spotless/pull/2973))
+
 ### Added
 - Add support for AsciiDoc formatting via `adocfmt`. ([#2960](https://github.com/diffplug/spotless/pull/2960))
 - `<flexmark>` step now supports arbitrary formatter options via `<formatterOptions>`. ([#2968](https://github.com/diffplug/spotless/pull/2968))