diff --git a/promisor-remote.c b/promisor-remote.c
index 6a0a61382f..ba80240f12 100644
--- a/promisor-remote.c
+++ b/promisor-remote.c
@@ -323,13 +323,15 @@ static void promisor_info_vecs(struct repository *repo,
 	promisor_remote_init(repo);
 
 	for (r = repo->promisor_remote_config->promisors; r; r = r->next) {
-		char *url;
+		const char *url;
 		char *url_key = xstrfmt("remote.%s.url", r->name);
 
-		strvec_push(names, r->name);
-		strvec_push(urls, git_config_get_string(url_key, &url) ? NULL : url);
+		/* Only add remotes with a non empty URL */
+		if (!git_config_get_string_tmp(url_key, &url) && *url) {
+			strvec_push(names, r->name);
+			strvec_push(urls, url);
+		}
 
-		free(url);
 		free(url_key);
 	}
 }
@@ -356,10 +358,8 @@ char *promisor_remote_info(struct repository *repo)
 			strbuf_addch(&sb, ';');
 		strbuf_addstr(&sb, "name=");
 		strbuf_addstr_urlencode(&sb, names.v[i], allow_unsanitized);
-		if (urls.v[i]) {
-			strbuf_addstr(&sb, ",url=");
-			strbuf_addstr_urlencode(&sb, urls.v[i], allow_unsanitized);
-		}
+		strbuf_addstr(&sb, ",url=");
+		strbuf_addstr_urlencode(&sb, urls.v[i], allow_unsanitized);
 	}
 
 	strvec_clear(&names);
diff --git a/t/t5710-promisor-remote-capability.sh b/t/t5710-promisor-remote-capability.sh
index d2cc69a17e..05ae96d1f7 100755
--- a/t/t5710-promisor-remote-capability.sh
+++ b/t/t5710-promisor-remote-capability.sh
@@ -193,6 +193,25 @@ test_expect_success "clone with 'KnownName' and different remote names" '
 	initialize_server 1 "$oid"
 '
 
+test_expect_success "clone with 'KnownName' and missing URL in the config" '
+	git -C server config promisor.advertise true &&
+
+	# Clone from server to create a client
+	# Lazy fetching by the client from the LOP will fail because of the
+	# missing URL in the client config, so the server will have to lazy
+	# fetch from the LOP.
+	GIT_NO_LAZY_FETCH=0 git clone -c remote.lop.promisor=true \
+		-c promisor.acceptfromserver=KnownName \
+		--no-local --filter="blob:limit=5k" server client &&
+	test_when_finished "rm -rf client" &&
+
+	# Check that the largest object is not missing on the server
+	check_missing_objects server 0 "" &&
+
+	# Reinitialize server so that the largest object is missing again
+	initialize_server 1 "$oid"
+'
+
 test_expect_success "clone with promisor.acceptfromserver set to 'KnownUrl'" '
 	git -C server config promisor.advertise true &&
 
@@ -228,6 +247,46 @@ test_expect_success "clone with 'KnownUrl' and different remote urls" '
 	initialize_server 1 "$oid"
 '
 
+test_expect_success "clone with 'KnownUrl' and url not configured on the server" '
+	git -C server config promisor.advertise true &&
+
+	git -C server config unset remote.lop.url &&
+	test_when_finished "git -C server config set remote.lop.url \"file://$(pwd)/lop\"" &&
+
+	# Clone from server to create a client
+	# It should fail because the client will reject the LOP as URLs are
+	# different, and the server cannot lazy fetch as the LOP URL is
+	# missing, so the remote name will be used instead which will fail.
+	test_must_fail env GIT_NO_LAZY_FETCH=0 git clone -c remote.lop.promisor=true \
+		-c remote.lop.fetch="+refs/heads/*:refs/remotes/lop/*" \
+		-c remote.lop.url="file://$(pwd)/lop" \
+		-c promisor.acceptfromserver=KnownUrl \
+		--no-local --filter="blob:limit=5k" server client &&
+
+	# Check that the largest object is still missing on the server
+	check_missing_objects server 1 "$oid"
+'
+
+test_expect_success "clone with 'KnownUrl' and empty url, so not advertised" '
+	git -C server config promisor.advertise true &&
+
+	git -C server config set remote.lop.url "" &&
+	test_when_finished "git -C server config set remote.lop.url \"file://$(pwd)/lop\"" &&
+
+	# Clone from server to create a client
+	# It should fail because the client will reject the LOP as an empty URL is
+	# not advertised, and the server cannot lazy fetch as the LOP URL is empty,
+	# so the remote name will be used instead which will fail.
+	test_must_fail env GIT_NO_LAZY_FETCH=0 git clone -c remote.lop.promisor=true \
+		-c remote.lop.fetch="+refs/heads/*:refs/remotes/lop/*" \
+		-c remote.lop.url="file://$(pwd)/lop" \
+		-c promisor.acceptfromserver=KnownUrl \
+		--no-local --filter="blob:limit=5k" server client &&
+
+	# Check that the largest object is still missing on the server
+	check_missing_objects server 1 "$oid"
+'
+
 test_expect_success "clone with promisor.advertise set to 'true' but don't delete the client" '
 	git -C server config promisor.advertise true &&
 
