diff --git a/models/pull.go b/models/pull.go
index bb5bb118122fa..8177daf1b528d 100644
--- a/models/pull.go
+++ b/models/pull.go
@@ -588,7 +588,7 @@ func (pr *PullRequest) IsWorkInProgress() bool {
 // HasWorkInProgressPrefix determines if the given PR title has a Work In Progress prefix
 func HasWorkInProgressPrefix(title string) bool {
 	for _, prefix := range setting.Repository.PullRequest.WorkInProgressPrefixes {
-		if strings.HasPrefix(strings.ToUpper(title), prefix) {
+		if strings.HasPrefix(strings.ToUpper(title), strings.ToUpper(prefix)) {
 			return true
 		}
 	}