diff --git a/src/libsystemd-network/dhcp6-internal.h b/src/libsystemd-network/dhcp6-internal.h
index db80585a22c..8b651636caf 100644
--- a/src/libsystemd-network/dhcp6-internal.h
+++ b/src/libsystemd-network/dhcp6-internal.h
@@ -97,6 +97,7 @@ int dhcp6_option_append(uint8_t **buf, size_t *buflen, uint16_t code,
 int dhcp6_option_append_ia(uint8_t **buf, size_t *buflen, const DHCP6IA *ia);
 int dhcp6_option_append_pd(uint8_t *buf, size_t len, const DHCP6IA *pd, DHCP6Address *hint_pd_prefix);
 int dhcp6_option_append_fqdn(uint8_t **buf, size_t *buflen, const char *fqdn);
+int dhcp6_option_append_user_class(uint8_t **buf, size_t *buflen, char **user_class);
 int dhcp6_option_parse(uint8_t **buf, size_t *buflen, uint16_t *optcode,
                        size_t *optlen, uint8_t **optvalue);
 int dhcp6_option_parse_status(DHCP6Option *option, size_t len);
diff --git a/src/libsystemd-network/dhcp6-option.c b/src/libsystemd-network/dhcp6-option.c
index 3b7c89edd7b..d1a02da35fd 100644
--- a/src/libsystemd-network/dhcp6-option.c
+++ b/src/libsystemd-network/dhcp6-option.c
@@ -167,6 +167,36 @@ int dhcp6_option_append_fqdn(uint8_t **buf, size_t *buflen, const char *fqdn) {
         return r;
 }
 
+int dhcp6_option_append_user_class(uint8_t **buf, size_t *buflen, char **user_class) {
+        _cleanup_free_ uint8_t *p = NULL;
+        size_t total = 0, offset = 0;
+        char **s;
+
+        assert_return(buf && *buf && buflen && user_class, -EINVAL);
+
+        STRV_FOREACH(s, user_class) {
+                size_t len = strlen(*s);
+                uint8_t *q;
+
+                if (len > 0xffff)
+                        return -ENAMETOOLONG;
+
+                q = realloc(p, total + len + 2);
+                if (!q)
+                        return -ENOMEM;
+
+                p = q;
+
+                unaligned_write_be16(&p[offset], len);
+                memcpy(&p[offset + 2], *s, len);
+
+                offset += 2 + len;
+                total += 2 + len;
+        }
+
+        return dhcp6_option_append(buf, buflen, SD_DHCP6_OPTION_USER_CLASS, total, p);
+}
+
 int dhcp6_option_append_pd(uint8_t *buf, size_t len, const DHCP6IA *pd, DHCP6Address *hint_pd_prefix) {
         DHCP6Option *option = (DHCP6Option *)buf;
         size_t i = sizeof(*option) + sizeof(pd->ia_pd);
diff --git a/src/libsystemd-network/sd-dhcp6-client.c b/src/libsystemd-network/sd-dhcp6-client.c
index 51716c28bb6..0240f1b7c7d 100644
--- a/src/libsystemd-network/sd-dhcp6-client.c
+++ b/src/libsystemd-network/sd-dhcp6-client.c
@@ -67,6 +67,7 @@ struct sd_dhcp6_client {
         size_t req_opts_len;
         char *fqdn;
         char *mudurl;
+        char **user_class;
         sd_event_source *receive_message;
         usec_t retransmit_time;
         uint8_t retransmit_count;
@@ -385,6 +386,27 @@ int sd_dhcp6_client_set_request_mud_url(sd_dhcp6_client *client, const char *mud
         return free_and_strdup(&client->mudurl, mudurl);
 }
 
+int sd_dhcp6_client_set_request_user_class(sd_dhcp6_client *client, char **user_class) {
+        _cleanup_strv_free_ char **s = NULL;
+        char **p;
+
+        assert_return(client, -EINVAL);
+        assert_return(client->state == DHCP6_STATE_STOPPED, -EBUSY);
+        assert_return(user_class, -EINVAL);
+
+        STRV_FOREACH(p, user_class)
+                if (strlen(*p) > UINT16_MAX)
+                        return -ENAMETOOLONG;
+
+        s = strv_copy((char **) user_class);
+        if (!s)
+                return -ENOMEM;
+
+        client->user_class = TAKE_PTR(s);
+
+        return 0;
+}
+
 int sd_dhcp6_client_get_prefix_delegation(sd_dhcp6_client *client, int *delegation) {
         assert_return(client, -EINVAL);
         assert_return(delegation, -EINVAL);
@@ -565,6 +587,12 @@ static int client_send_message(sd_dhcp6_client *client, usec_t time_now) {
                                 return r;
                 }
 
+                if (client->user_class) {
+                        r = dhcp6_option_append_user_class(&opt, &optlen, client->user_class);
+                        if (r < 0)
+                                return r;
+                }
+
                 if (FLAGS_SET(client->request, DHCP6_REQUEST_IA_PD)) {
                         r = dhcp6_option_append_pd(opt, optlen, &client->ia_pd, &client->hint_pd_prefix);
                         if (r < 0)
@@ -611,6 +639,12 @@ static int client_send_message(sd_dhcp6_client *client, usec_t time_now) {
                                 return r;
                 }
 
+                if (client->user_class) {
+                        r = dhcp6_option_append_user_class(&opt, &optlen, client->user_class);
+                        if (r < 0)
+                                return r;
+                }
+
                 if (FLAGS_SET(client->request, DHCP6_REQUEST_IA_PD)) {
                         r = dhcp6_option_append_pd(opt, optlen, &client->lease->pd, NULL);
                         if (r < 0)
@@ -645,6 +679,12 @@ static int client_send_message(sd_dhcp6_client *client, usec_t time_now) {
                                 return r;
                 }
 
+                if (client->user_class) {
+                        r = dhcp6_option_append_user_class(&opt, &optlen, client->user_class);
+                        if (r < 0)
+                                return r;
+                }
+
                 if (FLAGS_SET(client->request, DHCP6_REQUEST_IA_PD)) {
                         r = dhcp6_option_append_pd(opt, optlen, &client->lease->pd, NULL);
                         if (r < 0)
@@ -1602,7 +1642,10 @@ static sd_dhcp6_client *dhcp6_client_free(sd_dhcp6_client *client) {
         free(client->req_opts);
         free(client->fqdn);
         free(client->mudurl);
+
         ordered_hashmap_free(client->extra_options);
+        strv_free(client->user_class);
+
         return mfree(client);
 }
 
diff --git a/src/systemd/sd-dhcp6-client.h b/src/systemd/sd-dhcp6-client.h
index d365fc76380..8011457b761 100644
--- a/src/systemd/sd-dhcp6-client.h
+++ b/src/systemd/sd-dhcp6-client.h
@@ -125,6 +125,10 @@ int sd_dhcp6_client_set_request_option(
 int sd_dhcp6_client_set_request_mud_url(
                 sd_dhcp6_client *client,
                 const char *mudurl);
+
+int sd_dhcp6_client_set_request_user_class(
+                sd_dhcp6_client *client,
+                char** user_class);
 int sd_dhcp6_client_set_prefix_delegation_hint(
                 sd_dhcp6_client *client,
                 uint8_t prefixlen,