diff --git a/src/migration/migrations/2021-08-17T052508Z_OTTUniqueConstraint.go b/src/migration/migrations/2021-08-17T052508Z_OTTUniqueConstraint.go
new file mode 100644
index 00000000..6fa5aa1c
--- /dev/null
+++ b/src/migration/migrations/2021-08-17T052508Z_OTTUniqueConstraint.go
@@ -0,0 +1,46 @@
+package migrations
+
+import (
+	"context"
+	"time"
+
+	"git.handmade.network/hmn/hmn/src/migration/types"
+	"git.handmade.network/hmn/hmn/src/oops"
+	"github.com/jackc/pgx/v4"
+)
+
+func init() {
+	registerMigration(OTTUniqueConstraint{})
+}
+
+type OTTUniqueConstraint struct{}
+
+func (m OTTUniqueConstraint) Version() types.MigrationVersion {
+	return types.MigrationVersion(time.Date(2021, 8, 17, 5, 25, 8, 0, time.UTC))
+}
+
+func (m OTTUniqueConstraint) Name() string {
+	return "OTTUniqueConstraint"
+}
+
+func (m OTTUniqueConstraint) Description() string {
+	return "Add userid+type unique constraint to onetimetoken"
+}
+
+func (m OTTUniqueConstraint) Up(ctx context.Context, tx pgx.Tx) error {
+	_, err := tx.Exec(ctx,
+		`
+		DROP INDEX handmade_onetimetoken_ownerid_type;
+		ALTER TABLE handmade_onetimetoken
+			ADD CONSTRAINT handmade_onetimetoken_ownerid_type UNIQUE(owner_id, token_type);
+		`,
+	)
+	if err != nil {
+		return oops.New(err, "failed to replace index with unique constraint")
+	}
+	return nil
+}
+
+func (m OTTUniqueConstraint) Down(ctx context.Context, tx pgx.Tx) error {
+	panic("Implement me")
+}