diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.test.ts b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.test.ts
index ddfc23b5aa6285..bb20e0e639aa2a 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.test.ts
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.test.ts
@@ -297,7 +297,25 @@ describe('CrawlCustomSettingsFlyoutLogic', () => {
     });
 
     describe('startCustomCrawl', () => {
-      it('starts a custom crawl with the user set values', async () => {
+      it('can start a custom crawl for selected domains', async () => {
+        mount({
+          includeSitemapsInRobotsTxt: true,
+          maxCrawlDepth: 5,
+          selectedDomainUrls: ['https://www.elastic.co', 'https://swiftype.com'],
+        });
+        jest.spyOn(CrawlerLogic.actions, 'startCrawl');
+
+        CrawlCustomSettingsFlyoutLogic.actions.startCustomCrawl();
+        await nextTick();
+
+        expect(CrawlerLogic.actions.startCrawl).toHaveBeenCalledWith({
+          domain_allowlist: ['https://www.elastic.co', 'https://swiftype.com'],
+          max_crawl_depth: 5,
+          sitemap_discovery_disabled: false,
+        });
+      });
+
+      it('can start a custom crawl selected domains, sitemaps, and seed urls', async () => {
         mount({
           includeSitemapsInRobotsTxt: true,
           maxCrawlDepth: 5,
diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.ts b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.ts
index f22dcc7487af3d..3b04e1b28c17eb 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.ts
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/components/crawl_custom_settings_flyout/crawl_custom_settings_flyout_logic.ts
@@ -11,7 +11,7 @@ import { flashAPIErrors } from '../../../../../shared/flash_messages';
 import { HttpLogic } from '../../../../../shared/http';
 import { EngineLogic } from '../../../engine';
 
-import { CrawlerLogic } from '../../crawler_logic';
+import { CrawlerLogic, CrawlRequestOverrides } from '../../crawler_logic';
 import { DomainConfig, DomainConfigFromServer } from '../../types';
 import { domainConfigServerToClient } from '../../utils';
 import { extractDomainAndEntryPointFromUrl } from '../add_domain/utils';
@@ -213,13 +213,23 @@ export const CrawlCustomSettingsFlyoutLogic = kea<
       actions.fetchDomainConfigData();
     },
     startCustomCrawl: () => {
-      CrawlerLogic.actions.startCrawl({
-        domain_allowlist: values.selectedDomainUrls,
-        max_crawl_depth: values.maxCrawlDepth,
-        seed_urls: [...values.selectedEntryPointUrls, ...values.customEntryPointUrls],
-        sitemap_urls: [...values.selectedSitemapUrls, ...values.customSitemapUrls],
+      const overrides: CrawlRequestOverrides = {
         sitemap_discovery_disabled: !values.includeSitemapsInRobotsTxt,
-      });
+        max_crawl_depth: values.maxCrawlDepth,
+        domain_allowlist: values.selectedDomainUrls,
+      };
+
+      const seedUrls = [...values.selectedEntryPointUrls, ...values.customEntryPointUrls];
+      if (seedUrls.length > 0) {
+        overrides.seed_urls = seedUrls;
+      }
+
+      const sitemapUrls = [...values.selectedSitemapUrls, ...values.customSitemapUrls];
+      if (sitemapUrls.length > 0) {
+        overrides.sitemap_urls = sitemapUrls;
+      }
+
+      CrawlerLogic.actions.startCrawl(overrides);
     },
   }),
 });
diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/crawler_logic.ts b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/crawler_logic.ts
index 68b1cb6ec9b267..2d1b8a9e7aa27e 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/crawler_logic.ts
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/crawler/crawler_logic.ts
@@ -33,7 +33,7 @@ const ACTIVE_STATUSES = [
   CrawlerStatus.Canceling,
 ];
 
-interface CrawlRequestOverrides {
+export interface CrawlRequestOverrides {
   domain_allowlist?: string[];
   max_crawl_depth?: number;
   seed_urls?: string[];