diff --git a/fastify.d.ts b/fastify.d.ts
index aba742671b..de5c82662f 100644
--- a/fastify.d.ts
+++ b/fastify.d.ts
@@ -98,6 +98,7 @@ export type FastifyServerOptions<
   connectionTimeout?: number,
   keepAliveTimeout?: number,
   maxRequestsPerSocket?: number,
+  forceCloseConnections?: boolean,
   requestTimeout?: number,
   pluginTimeout?: number,
   bodyLimit?: number,
diff --git a/test/types/fastify.test-d.ts b/test/types/fastify.test-d.ts
index 07a50e7a6b..b7468733a8 100644
--- a/test/types/fastify.test-d.ts
+++ b/test/types/fastify.test-d.ts
@@ -57,6 +57,7 @@ fastify({ http2: true, https: {} }).inject({}, lightMyRequestCallback)
 expectAssignable<FastifyInstance<http2.Http2Server, http2.Http2ServerRequest, http2.Http2ServerResponse>>(fastify({ http2: true }))
 expectAssignable<FastifyInstance>(fastify({ ignoreTrailingSlash: true }))
 expectAssignable<FastifyInstance>(fastify({ connectionTimeout: 1000 }))
+expectAssignable<FastifyInstance>(fastify({ forceCloseConnections: true }))
 expectAssignable<FastifyInstance>(fastify({ keepAliveTimeout: 1000 }))
 expectAssignable<FastifyInstance>(fastify({ pluginTimeout: 1000 }))
 expectAssignable<FastifyInstance>(fastify({ bodyLimit: 100 }))
diff --git a/test/types/instance.test-d.ts b/test/types/instance.test-d.ts
index d134ba2332..0ff544a3f1 100644
--- a/test/types/instance.test-d.ts
+++ b/test/types/instance.test-d.ts
@@ -171,6 +171,7 @@ type InitialConfig = Readonly<{
   keepAliveTimeout?: number,
   bodyLimit?: number,
   caseSensitive?: boolean,
+  forceCloseConnections?: boolean,
   http2?: boolean,
   https?: boolean | Readonly<{ allowHTTP1: boolean }>,
   ignoreTrailingSlash?: boolean,
diff --git a/types/instance.d.ts b/types/instance.d.ts
index 8c2e984e8e..5d5d3de80a 100644
--- a/types/instance.d.ts
+++ b/types/instance.d.ts
@@ -427,6 +427,7 @@ export interface FastifyInstance<
   initialConfig: Readonly<{
     connectionTimeout?: number,
     keepAliveTimeout?: number,
+    forceCloseConnections?: boolean,
     bodyLimit?: number,
     caseSensitive?: boolean,
     http2?: boolean,