diff --git a/crypto/ts/ts_rsp_sign.c b/crypto/ts/ts_rsp_sign.c
index df09e17834..3c48352366 100644
--- a/crypto/ts/ts_rsp_sign.c
+++ b/crypto/ts/ts_rsp_sign.c
@@ -971,7 +971,7 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
 	if (precision > 0)
 	{
 		/* Add fraction of seconds (leave space for dot and null). */
-		BIO_snprintf(p, 2 + precision, ".%ld", usec);
+		BIO_snprintf(p, 2 + precision, ".%06ld", usec);
 		/* We cannot use the snprintf return value, 
 		   because it might have been truncated. */
 		p += strlen(p);