diff --git a/protocol/tailscale/dns_transport.go b/protocol/tailscale/dns_transport.go
index 6c4b551f..9edbfbc4 100644
--- a/protocol/tailscale/dns_transport.go
+++ b/protocol/tailscale/dns_transport.go
@@ -283,7 +283,7 @@ func (t *DNSTransport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.M
 		}
 	}
 	for domainSuffix, transports := range routes {
-		if strings.HasSuffix(question.Name, domainSuffix) {
+		if mDNS.IsSubDomain(domainSuffix, question.Name) {
 			if len(transports) == 0 {
 				return &mDNS.Msg{
 					MsgHdr: mDNS.MsgHdr{
diff --git a/service/resolved/transport.go b/service/resolved/transport.go
index bdc35551..f4beafd8 100644
--- a/service/resolved/transport.go
+++ b/service/resolved/transport.go
@@ -6,7 +6,6 @@ import (
 	"context"
 	"net/netip"
 	"os"
-	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -200,7 +199,7 @@ func (t *Transport) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg,
 			if domain.Domain == "." && domain.RoutingOnly && !t.acceptDefaultResolvers {
 				continue
 			}
-			if strings.HasSuffix(question.Name, domain.Domain) {
+			if mDNS.IsSubDomain(domain.Domain, question.Name) {
 				selectedLink = link
 			}
 		}