diff --git a/src/resolve/resolved-dns-question.c b/src/resolve/resolved-dns-question.c
index aefdaa0eeb7..8f5ebb4590d 100644
--- a/src/resolve/resolved-dns-question.c
+++ b/src/resolve/resolved-dns-question.c
@@ -50,6 +50,19 @@ int dns_question_add_raw(DnsQuestion *q, DnsResourceKey *key, DnsQuestionFlags f
         return 0;
 }
 
+static int dns_question_add_raw_all(DnsQuestion *a, DnsQuestion *b) {
+        DnsQuestionItem *item;
+        int r;
+
+        DNS_QUESTION_FOREACH_ITEM(item, b) {
+                r = dns_question_add_raw(a, item->key, item->flags);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
 int dns_question_add(DnsQuestion *q, DnsResourceKey *key, DnsQuestionFlags flags) {
         DnsQuestionItem *item;
         int r;
@@ -71,6 +84,19 @@ int dns_question_add(DnsQuestion *q, DnsResourceKey *key, DnsQuestionFlags flags
         return dns_question_add_raw(q, key, flags);
 }
 
+static int dns_question_add_all(DnsQuestion *a, DnsQuestion *b) {
+        DnsQuestionItem *item;
+        int r;
+
+        DNS_QUESTION_FOREACH_ITEM(item, b) {
+                r = dns_question_add(a, item->key, item->flags);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
 int dns_question_matches_rr(DnsQuestion *q, DnsResourceRecord *rr, const char *search_domain) {
         DnsResourceKey *key;
         int r;
@@ -486,3 +512,35 @@ void dns_question_dump(DnsQuestion *question, FILE *f) {
                 fputc('\n', f);
         }
 }
+
+int dns_question_merge(DnsQuestion *a, DnsQuestion *b, DnsQuestion **ret) {
+        _cleanup_(dns_question_unrefp) DnsQuestion *k = NULL;
+        int r;
+
+        assert(ret);
+
+        if (a == b || dns_question_size(b) <= 0) {
+                *ret = dns_question_ref(a);
+                return 0;
+        }
+
+        if (dns_question_size(a) <= 0) {
+                *ret = dns_question_ref(b);
+                return 0;
+        }
+
+        k = dns_question_new(dns_question_size(a) + dns_question_size(b));
+        if (!k)
+                return -ENOMEM;
+
+        r = dns_question_add_raw_all(k, a);
+        if (r < 0)
+                return r;
+
+        r = dns_question_add_all(k, b);
+        if (r < 0)
+                return r;
+
+        *ret = TAKE_PTR(k);
+        return 0;
+}
diff --git a/src/resolve/resolved-dns-question.h b/src/resolve/resolved-dns-question.h
index 31b8a2ec3ef..91bbeaed5bf 100644
--- a/src/resolve/resolved-dns-question.h
+++ b/src/resolve/resolved-dns-question.h
@@ -59,6 +59,8 @@ static inline bool dns_question_isempty(DnsQuestion *q) {
         return dns_question_size(q) <= 0;
 }
 
+int dns_question_merge(DnsQuestion *a, DnsQuestion *b, DnsQuestion **ret);
+
 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsQuestion*, dns_question_unref);
 
 #define _DNS_QUESTION_FOREACH(u, k, q)                                     \