diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceFilter.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceFilter.java
index 1f88656af..cc1db1df8 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceFilter.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceFilter.java
@@ -216,6 +216,9 @@ public class TraceFilter extends GenericFilterBean {
 	}
 
 	private boolean httpStatusSuccessful(HttpServletResponse response) {
+		if (response.getStatus() == 0) {
+			return false;
+		}
 		HttpStatus httpStatus = HttpStatus.valueOf(response.getStatus());
 		return httpStatus.is2xxSuccessful() || httpStatus.is3xxRedirection();
 	}
@@ -308,7 +311,8 @@ public class TraceFilter extends GenericFilterBean {
 			this.tracer.addTag(this.traceKeys.getHttp().getStatusCode(),
 					String.valueOf(HttpServletResponse.SC_INTERNAL_SERVER_ERROR));
 		}
-		else if ((httpStatus < 200) || (httpStatus > 399)) {
+		// only tag valid http statuses
+		else if (httpStatus >= 100 && (httpStatus < 200) || (httpStatus > 399)) {
 			this.tracer.addTag(this.traceKeys.getHttp().getStatusCode(),
 					String.valueOf(response.getStatus()));
 		}
diff --git a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/TraceFilterTests.java b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/TraceFilterTests.java
index 0add851d1..427b49424 100644
--- a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/TraceFilterTests.java
+++ b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/TraceFilterTests.java
@@ -131,6 +131,18 @@ public class TraceFilterTests {
 		then(TestSpanContextHolder.getCurrentSpan()).isNull();
 	}
 
+	@Test
+	public void shouldNotStoreHttpStatusCodeWhenResponseCodeHasNotYetBeenSet() throws Exception {
+		TraceFilter filter = new TraceFilter(this.tracer, this.traceKeys, this.spanReporter,
+				this.spanExtractor, this.spanInjector, this.httpTraceKeysInjector);
+		this.response.setStatus(0);
+		filter.doFilter(this.request, this.response, this.filterChain);
+
+		assertThat(this.span.tags()).doesNotContainKey("http.status_code");
+
+		then(TestSpanContextHolder.getCurrentSpan()).isNull();
+	}
+
 	@Test
 	public void startsNewTraceWithParentIdInHeaders() throws Exception {
 		this.request = builder()