diff --git a/web/src/main/java/org/springframework/security/web/server/transport/HttpsRedirectWebFilter.java b/web/src/main/java/org/springframework/security/web/server/transport/HttpsRedirectWebFilter.java
index d0b7b49846..99d72a22be 100644
--- a/web/src/main/java/org/springframework/security/web/server/transport/HttpsRedirectWebFilter.java
+++ b/web/src/main/java/org/springframework/security/web/server/transport/HttpsRedirectWebFilter.java
@@ -102,9 +102,10 @@ public final class HttpsRedirectWebFilter implements WebFilter {
 				UriComponentsBuilder.fromUri(exchange.getRequest().getURI());
 
 		if (port > 0) {
-			builder.port(Optional.ofNullable(this.portMapper.lookupHttpsPort(port))
-									.orElseThrow(() -> new IllegalStateException(
-										"HTTP Port '" + port + "' does not have a corresponding HTTPS Port")));
+			Optional.ofNullable(this.portMapper.lookupHttpsPort(port))
+					.map(builder::port)
+					.orElseThrow(() -> new IllegalStateException(
+							"HTTP Port '" + port + "' does not have a corresponding HTTPS Port"));
 		}
 
 		return builder.scheme("https").build().toUri();