diff --git a/handshake_manager.go b/handshake_manager.go
index 8d841756..481395a5 100644
--- a/handshake_manager.go
+++ b/handshake_manager.go
@@ -318,7 +318,7 @@ func (hm *HandshakeManager) handleOutbound(vpnIp netip.Addr, lighthouseTriggered
 		}
 
 		// Attempt a multiport handshake if we are past the TxHandshakeDelay attempts
-		if hm.multiPort.TxHandshake && hm.udpRaw != nil && hh.counter >= hm.multiPort.TxHandshakeDelay {
+		if hm.multiPort.TxHandshake && hm.udpRaw != nil && hh.counter >= hm.multiPort.TxHandshakeDelay && udp.RawSupported(addr) {
 			sentMultiport = true
 			// We need to re-allocate with 8 bytes at the start of SOCK_RAW
 			raw := hostinfo.HandshakePacket[0x80]
diff --git a/inside.go b/inside.go
index 32b02668..454b6d0c 100644
--- a/inside.go
+++ b/inside.go
@@ -414,7 +414,7 @@ func (f *Interface) sendNoMetrics(t header.MessageType, st header.MessageSubType
 	}
 
 	if remote.IsValid() {
-		if multiport {
+		if multiport && udp.RawSupported(remote) {
 			rawOut = rawOut[:len(out)+udp.RawOverhead]
 			port := udpPortGetter.UDPSendPort(f.multiPort.TxPorts)
 			err = f.udpRaw.WriteTo(rawOut, port, remote)
@@ -428,7 +428,7 @@ func (f *Interface) sendNoMetrics(t header.MessageType, st header.MessageSubType
 			)
 		}
 	} else if hr := hostinfo.GetRemote(); hr.IsValid() {
-		if multiport {
+		if multiport && udp.RawSupported(hr) {
 			rawOut = rawOut[:len(out)+udp.RawOverhead]
 			port := udpPortGetter.UDPSendPort(f.multiPort.TxPorts)
 			err = f.udpRaw.WriteTo(rawOut, port, hr)
diff --git a/udp/udp_raw.go b/udp/udp_raw.go
index 4c5c2879..b9408e8c 100644
--- a/udp/udp_raw.go
+++ b/udp/udp_raw.go
@@ -1,6 +1,9 @@
 package udp
 
-import mathrand "math/rand"
+import (
+	mathrand "math/rand"
+	"net/netip"
+)
 
 type SendPortGetter interface {
 	// UDPSendPort returns the port to use
@@ -14,3 +17,11 @@ func (randomSendPort) UDPSendPort(maxPort int) uint16 {
 }
 
 var RandomSendPort = randomSendPort{}
+
+// RawSupported reports whether (*RawConn).WriteTo can send to addr. The raw
+// socket only builds IPv4 headers, so IPv6 destinations must use the normal
+// UDP socket.
+func RawSupported(addr netip.AddrPort) bool {
+	a := addr.Addr()
+	return a.Is4() || a.Is4In6()
+}
diff --git a/udp/udp_raw_linux.go b/udp/udp_raw_linux.go
index 5093dd45..ff23fa12 100644
--- a/udp/udp_raw_linux.go
+++ b/udp/udp_raw_linux.go
@@ -76,6 +76,10 @@ func NewRawConn(l *slog.Logger, ip string, port int, basePort uint16) (*RawConn,
 // WriteTo must be called with raw leaving the first `udp.RawOverhead` bytes empty,
 // for the IP/UDP headers.
 func (u *RawConn) WriteTo(raw []byte, fromPort uint16, ip netip.AddrPort) error {
+	if !RawSupported(ip) {
+		return fmt.Errorf("raw socket does not support sending to %s", ip)
+	}
+
 	var rsa unix.RawSockaddrInet4
 	rsa.Family = unix.AF_INET
 	rsa.Addr = ip.Addr().As4()
diff --git a/udp/udp_raw_test.go b/udp/udp_raw_test.go
new file mode 100644
index 00000000..85c086bb
--- /dev/null
+++ b/udp/udp_raw_test.go
@@ -0,0 +1,15 @@
+package udp
+
+import (
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRawSupported(t *testing.T) {
+	assert.True(t, RawSupported(netip.MustParseAddrPort("1.2.3.4:4242")))
+	assert.True(t, RawSupported(netip.MustParseAddrPort("[::ffff:1.2.3.4]:4242")))
+	assert.False(t, RawSupported(netip.MustParseAddrPort("[2001:db8::1]:4242")))
+	assert.False(t, RawSupported(netip.AddrPort{}))
+}