diff --git a/command/repo.go b/command/repo.go
index 5e16f9645..4f8c51e0b 100644
--- a/command/repo.go
+++ b/command/repo.go
@@ -169,7 +169,7 @@ func addUpstreamRemote(parentRepo ghrepo.Interface, cloneDir string) error {
 	// TODO: support SSH remote URLs
 	upstreamURL := fmt.Sprintf("https://github.com/%s.git", ghrepo.FullName(parentRepo))
 
-	cloneCmd := git.GitCommand("-C", cloneDir, "remote", "add", "upstream", upstreamURL)
+	cloneCmd := git.GitCommand("-C", cloneDir, "remote", "add", "-f", "upstream", upstreamURL)
 	cloneCmd.Stdout = os.Stdout
 	cloneCmd.Stderr = os.Stderr
 	return run.PrepareCmd(cloneCmd).Run()
diff --git a/command/repo_test.go b/command/repo_test.go
index e52df1313..cf3fe3423 100644
--- a/command/repo_test.go
+++ b/command/repo_test.go
@@ -186,7 +186,7 @@ func TestRepoFork_outside_yes(t *testing.T) {
 	eq(t, output.Stderr(), "")
 
 	eq(t, strings.Join(cs.Calls[0].Args, " "), "git clone https://github.com/someone/repo.git")
-	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C repo remote add upstream https://github.com/OWNER/REPO.git")
+	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C repo remote add -f upstream https://github.com/OWNER/REPO.git")
 
 	test.ExpectLines(t, output.String(),
 		"Created fork someone/REPO",
@@ -219,7 +219,7 @@ func TestRepoFork_outside_survey_yes(t *testing.T) {
 	eq(t, output.Stderr(), "")
 
 	eq(t, strings.Join(cs.Calls[0].Args, " "), "git clone https://github.com/someone/repo.git")
-	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C repo remote add upstream https://github.com/OWNER/REPO.git")
+	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C repo remote add -f upstream https://github.com/OWNER/REPO.git")
 
 	test.ExpectLines(t, output.String(),
 		"Created fork someone/REPO",
@@ -484,7 +484,7 @@ func TestRepoClone_hasParent(t *testing.T) {
 	}
 
 	eq(t, cs.Count, 2)
-	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C REPO remote add upstream https://github.com/hubot/ORIG.git")
+	eq(t, strings.Join(cs.Calls[1].Args, " "), "git -C REPO remote add -f upstream https://github.com/hubot/ORIG.git")
 }
 
 func TestRepoCreate(t *testing.T) {