diff --git a/library/lmots.c b/library/lmots.c
index fe01bf6..8e56696 100644
--- a/library/lmots.c
+++ b/library/lmots.c
@@ -194,7 +194,7 @@
         goto exit;
 
     status = psa_hash_finish( &op, out,
-                              MBEDTLS_LMOTS_P_SIG_DIGIT_COUNT(params->type),
+                              MBEDTLS_LMOTS_N_HASH_LEN(params->type),
                               &output_hash_len );
     ret = mbedtls_lms_error_from_psa( status );
     if( ret != 0 )