diff --git a/.changelog/10824.txt b/.changelog/10824.txt
new file mode 100644
index 0000000000..53da4296bb
--- /dev/null
+++ b/.changelog/10824.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+acl: fixes a bug that prevented the default user token from being used to authorize service registration for connect proxies.
+```
diff --git a/agent/agent.go b/agent/agent.go
index 8dc6c1f0af..87c6d3a225 100644
--- a/agent/agent.go
+++ b/agent/agent.go
@@ -559,6 +559,7 @@ func (a *Agent) Start(ctx context.Context) error {
 		Health: a.rpcClientHealth,
 		Logger: a.logger.Named(logging.ProxyConfig),
 		State:  a.State,
+		Tokens: a.baseDeps.Tokens,
 		Source: &structs.QuerySource{
 			Datacenter: a.config.Datacenter,
 			Segment:    a.config.SegmentName,
diff --git a/agent/proxycfg/manager.go b/agent/proxycfg/manager.go
index 922e73ed57..aca122b0c5 100644
--- a/agent/proxycfg/manager.go
+++ b/agent/proxycfg/manager.go
@@ -9,6 +9,7 @@ import (
 	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/local"
 	"github.com/hashicorp/consul/agent/structs"
+	"github.com/hashicorp/consul/agent/token"
 	"github.com/hashicorp/consul/tlsutil"
 )
 
@@ -73,6 +74,9 @@ type ManagerConfig struct {
 	// logger is the agent's logger to be used for logging logs.
 	Logger          hclog.Logger
 	TLSConfigurator *tlsutil.Configurator
+	// Tokens configured on the local agent. Used to look up the agent token if
+	// a service is registered without a token.
+	Tokens *token.Store
 
 	// IntentionDefaultAllow is set by the agent so that we can pass this
 	// information to proxies that need to make intention decisions on their
@@ -156,7 +160,7 @@ func (m *Manager) syncState() {
 		// know that so we'd need to set it here if not during registration of the
 		// proxy service. Sidecar Service in the interim can do that, but we should
 		// validate more generally that that is always true.
-		err := m.ensureProxyServiceLocked(svc, m.State.ServiceToken(sid))
+		err := m.ensureProxyServiceLocked(svc)
 		if err != nil {
 			m.Logger.Error("failed to watch proxy service",
 				"service", sid.String(),
@@ -175,10 +179,18 @@ func (m *Manager) syncState() {
 }
 
 // ensureProxyServiceLocked adds or changes the proxy to our state.
-func (m *Manager) ensureProxyServiceLocked(ns *structs.NodeService, token string) error {
+func (m *Manager) ensureProxyServiceLocked(ns *structs.NodeService) error {
 	sid := ns.CompoundServiceID()
-	state, ok := m.proxies[sid]
 
+	// Retrieve the token used to register the service, or fallback to the
+	// default user token. This token is expected to match the token used in
+	// the xDS request for this data.
+	token := m.State.ServiceToken(sid)
+	if token == "" {
+		token = m.Tokens.UserToken()
+	}
+
+	state, ok := m.proxies[sid]
 	if ok {
 		if !state.Changed(ns, token) {
 			// No change
diff --git a/agent/proxycfg/manager_test.go b/agent/proxycfg/manager_test.go
index 658bad43ba..8cd19a5139 100644
--- a/agent/proxycfg/manager_test.go
+++ b/agent/proxycfg/manager_test.go
@@ -557,3 +557,48 @@ func testGenCacheKey(req cache.Request) string {
 	info := req.CacheInfo()
 	return path.Join(info.Key, info.Datacenter)
 }
+
+func TestManager_SyncState_DefaultToken(t *testing.T) {
+	types := NewTestCacheTypes(t)
+	c := TestCacheWithTypes(t, types)
+	logger := testutil.Logger(t)
+	tokens := new(token.Store)
+	tokens.UpdateUserToken("default-token", token.TokenSourceConfig)
+
+	state := local.NewState(local.Config{}, logger, tokens)
+	state.TriggerSyncChanges = func() {}
+
+	m, err := NewManager(ManagerConfig{
+		Cache:  c,
+		Health: &health.Client{Cache: c, CacheName: cachetype.HealthServicesName},
+		State:  state,
+		Tokens: tokens,
+		Source: &structs.QuerySource{Datacenter: "dc1"},
+		Logger: logger,
+	})
+	require.NoError(t, err)
+	defer m.Close()
+
+	srv := &structs.NodeService{
+		Kind:    structs.ServiceKindConnectProxy,
+		ID:      "web-sidecar-proxy",
+		Service: "web-sidecar-proxy",
+		Port:    9999,
+		Meta:    map[string]string{},
+		Proxy: structs.ConnectProxyConfig{
+			DestinationServiceID:   "web",
+			DestinationServiceName: "web",
+			LocalServiceAddress:    "127.0.0.1",
+			LocalServicePort:       8080,
+			Config: map[string]interface{}{
+				"foo": "bar",
+			},
+		},
+	}
+
+	err = state.AddServiceWithChecks(srv, nil, "")
+	require.NoError(t, err)
+	m.syncState()
+
+	require.Equal(t, "default-token", m.proxies[srv.CompoundServiceID()].serviceInstance.token)
+}