diff --git a/include/patty/ax25.h b/include/patty/ax25.h
index 2d86904..af57d26 100644
--- a/include/patty/ax25.h
+++ b/include/patty/ax25.h
@@ -84,4 +84,8 @@ int patty_ax25_ntop(const patty_ax25_addr *addr,
 void patty_ax25_addr_hash(uint32_t *hash,
                           const patty_ax25_addr *addr);
 
+size_t patty_ax25_addr_copy(void *buf,
+                            patty_ax25_addr *addr,
+                            uint8_t ssid_flags);
+
 #endif /* _PATTY_AX25_H */
diff --git a/src/ax25.c b/src/ax25.c
index ff60609..e51499e 100644
--- a/src/ax25.c
+++ b/src/ax25.c
@@ -106,3 +106,17 @@ void patty_ax25_addr_hash(uint32_t *hash, const patty_ax25_addr *addr) {
 
     hash_byte(hash, PATTY_AX25_ADDR_SSID_NUMBER(addr->ssid));
 }
+
+size_t patty_ax25_addr_copy(void *buf,
+                            patty_ax25_addr *addr,
+                            uint8_t ssid_flags) {
+    size_t encoded = 0;
+
+    memcpy(buf, addr->callsign, sizeof(addr->callsign));
+
+    encoded += sizeof(addr->callsign);
+
+    ((uint8_t *)buf)[encoded++] = ssid_flags | 0x60 | (addr->ssid & 0x1e);
+
+    return encoded;
+}