diff --git a/spring-web/src/main/java/org/springframework/web/context/request/ServletWebRequest.java b/spring-web/src/main/java/org/springframework/web/context/request/ServletWebRequest.java
index 52646ced870..0e070c3c806 100644
--- a/spring-web/src/main/java/org/springframework/web/context/request/ServletWebRequest.java
+++ b/spring-web/src/main/java/org/springframework/web/context/request/ServletWebRequest.java
@@ -214,12 +214,12 @@ public class ServletWebRequest extends ServletRequestAttributes implements Nativ
 		// Evaluate conditions in order of precedence.
 		// See https://datatracker.ietf.org/doc/html/rfc9110#section-13.2.2
 		if (validateIfMatch(eTag)) {
-			updateResponseStateChanging();
+			updateResponseStateChanging(eTag, lastModifiedTimestamp);
 			return this.notModified;
 		}
 		// 2) If-Unmodified-Since
 		else if (validateIfUnmodifiedSince(lastModifiedTimestamp)) {
-			updateResponseStateChanging();
+			updateResponseStateChanging(eTag, lastModifiedTimestamp);
 			return this.notModified;
 		}
 		// 3) If-None-Match
@@ -309,10 +309,13 @@ public class ServletWebRequest extends ServletRequestAttributes implements Nativ
 		return first.equals(second);
 	}
 
-	private void updateResponseStateChanging() {
+	private void updateResponseStateChanging(String eTag, long lastModifiedTimestamp) {
 		if (this.notModified && getResponse() != null) {
 			getResponse().setStatus(HttpStatus.PRECONDITION_FAILED.value());
 		}
+		else {
+			addCachingResponseHeaders(eTag, lastModifiedTimestamp);
+		}
 	}
 
 	private boolean validateIfUnmodifiedSince(long lastModifiedTimestamp) {
@@ -347,13 +350,17 @@ public class ServletWebRequest extends ServletRequestAttributes implements Nativ
 				getResponse().setStatus(isHttpGetOrHead ?
 						HttpStatus.NOT_MODIFIED.value() : HttpStatus.PRECONDITION_FAILED.value());
 			}
-			if (isHttpGetOrHead) {
-				if (lastModifiedTimestamp > 0 && parseDateValue(getResponse().getHeader(HttpHeaders.LAST_MODIFIED)) == -1) {
-					getResponse().setDateHeader(HttpHeaders.LAST_MODIFIED, lastModifiedTimestamp);
-				}
-				if (StringUtils.hasLength(eTag) && getResponse().getHeader(HttpHeaders.ETAG) == null) {
-					getResponse().setHeader(HttpHeaders.ETAG, padEtagIfNecessary(eTag));
-				}
+			addCachingResponseHeaders(eTag, lastModifiedTimestamp);
+		}
+	}
+
+	private void addCachingResponseHeaders(String eTag, long lastModifiedTimestamp) {
+		if (SAFE_METHODS.contains(getRequest().getMethod())) {
+			if (lastModifiedTimestamp > 0 && parseDateValue(getResponse().getHeader(HttpHeaders.LAST_MODIFIED)) == -1) {
+				getResponse().setDateHeader(HttpHeaders.LAST_MODIFIED, lastModifiedTimestamp);
+			}
+			if (StringUtils.hasLength(eTag) && getResponse().getHeader(HttpHeaders.ETAG) == null) {
+				getResponse().setHeader(HttpHeaders.ETAG, padEtagIfNecessary(eTag));
 			}
 		}
 	}
diff --git a/spring-web/src/main/java/org/springframework/web/server/adapter/DefaultServerWebExchange.java b/spring-web/src/main/java/org/springframework/web/server/adapter/DefaultServerWebExchange.java
index f43036302a9..06b949f955e 100644
--- a/spring-web/src/main/java/org/springframework/web/server/adapter/DefaultServerWebExchange.java
+++ b/spring-web/src/main/java/org/springframework/web/server/adapter/DefaultServerWebExchange.java
@@ -259,12 +259,12 @@ public class DefaultServerWebExchange implements ServerWebExchange {
 		// See https://datatracker.ietf.org/doc/html/rfc9110#section-13.2.2
 		// 1) If-Match
 		if (validateIfMatch(eTag)) {
-			updateResponseStateChanging();
+			updateResponseStateChanging(eTag, lastModified);
 			return this.notModified;
 		}
 		// 2) If-Unmodified-Since
 		else if (validateIfUnmodifiedSince(lastModified)) {
-			updateResponseStateChanging();
+			updateResponseStateChanging(eTag, lastModified);
 			return this.notModified;
 		}
 		// 3) If-None-Match
@@ -346,10 +346,13 @@ public class DefaultServerWebExchange implements ServerWebExchange {
 		return first.equals(second);
 	}
 
-	private void updateResponseStateChanging() {
+	private void updateResponseStateChanging(String eTag, Instant lastModified) {
 		if (this.notModified) {
 			getResponse().setStatusCode(HttpStatus.PRECONDITION_FAILED);
 		}
+		else {
+			addCachingResponseHeaders(eTag, lastModified);
+		}
 	}
 
 	private boolean validateIfNoneMatch(@Nullable String eTag) {
@@ -371,7 +374,11 @@ public class DefaultServerWebExchange implements ServerWebExchange {
 			getResponse().setStatusCode(isSafeMethod ?
 					HttpStatus.NOT_MODIFIED : HttpStatus.PRECONDITION_FAILED);
 		}
-		if (isSafeMethod) {
+		addCachingResponseHeaders(eTag, lastModified);
+	}
+
+	private void addCachingResponseHeaders(@Nullable String eTag, Instant lastModified) {
+		if (SAFE_METHODS.contains(getRequest().getMethod())) {
 			if (lastModified.isAfter(Instant.EPOCH) && getResponseHeaders().getLastModified() == -1) {
 				getResponseHeaders().setLastModified(lastModified.toEpochMilli());
 			}
diff --git a/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java b/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java
index 94447017e91..81cdb8e47f9 100644
--- a/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java
+++ b/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java
@@ -126,6 +126,16 @@ class ServletWebRequestHttpMethodsTests {
 		assertPreconditionFailed();
 	}
 
+	@SafeHttpMethodsTest
+	void ifUnModifiedSinceShouldSetHeadersWithSafeMethod(String method) {
+		setUpRequest(method);
+		Instant now = Instant.now().truncatedTo(ChronoUnit.SECONDS);
+		Instant oneMinuteAgo = now.minus(1, ChronoUnit.MINUTES);
+		servletRequest.addHeader(HttpHeaders.IF_UNMODIFIED_SINCE, now.toEpochMilli());
+		assertThat(request.checkNotModified(oneMinuteAgo.toEpochMilli())).isFalse();
+		assertOkWithLastModified(oneMinuteAgo);
+	}
+
 	@SafeHttpMethodsTest
 	void ifNoneMatchShouldMatchIdenticalETagValue(String method) {
 		setUpRequest(method);
diff --git a/spring-web/src/test/java/org/springframework/web/server/adapter/DefaultServerWebExchangeCheckNotModifiedTests.java b/spring-web/src/test/java/org/springframework/web/server/adapter/DefaultServerWebExchangeCheckNotModifiedTests.java
index 97b963bd32f..2ab3a3a43c9 100644
--- a/spring-web/src/test/java/org/springframework/web/server/adapter/DefaultServerWebExchangeCheckNotModifiedTests.java
+++ b/spring-web/src/test/java/org/springframework/web/server/adapter/DefaultServerWebExchangeCheckNotModifiedTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -307,4 +307,18 @@ class DefaultServerWebExchangeCheckNotModifiedTests {
 		assertThat(exchange.getResponse().getHeaders().getLastModified()).isEqualTo(-1);
 	}
 
+	@Test
+	void checkNotModifiedTimestampConditionalWithSafeMethod() throws Exception {
+		String eTag = "\"Foo\"";
+		Instant oneMinuteAgo = currentDate.minusSeconds(60);
+		MockServerHttpRequest request = MockServerHttpRequest.get("/")
+				.ifUnmodifiedSince(currentDate.toEpochMilli()).build();
+		MockServerWebExchange exchange = MockServerWebExchange.from(request);
+		assertThat(exchange.checkNotModified(eTag, oneMinuteAgo)).isFalse();
+		assertThat(exchange.getResponse().getStatusCode()).isNull();
+		assertThat(exchange.getResponse().getHeaders().getLastModified()).isEqualTo(oneMinuteAgo.toEpochMilli());
+		assertThat(exchange.getResponse().getHeaders().getETag()).isEqualTo(eTag);
+	}
+
+
 }