diff --git a/CHANGELOG.md b/CHANGELOG.md
index c2dd6795c..acd59572f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Upgraded `tar` to `^7.5.16`. [#1338](https://github.com/sourcebot-dev/sourcebot/pull/1338)
 - Upgraded `esbuild` to `^0.28.1`. [#1342](https://github.com/sourcebot-dev/sourcebot/pull/1342)
 - Enabled Next.js version skew protection to fix "Failed to load chunk" errors during rolling deploys. [#1346](https://github.com/sourcebot-dev/sourcebot/pull/1346)
+- Split GitLab group sync into bounded direct-project and subgroup page fetches to avoid timeouts on large namespaces. [#1351](https://github.com/sourcebot-dev/sourcebot/pull/1351)
 
 ## [5.0.3] - 2026-06-17
 
diff --git a/packages/backend/src/gitlab.test.ts b/packages/backend/src/gitlab.test.ts
index a502488df..7473084cd 100644
--- a/packages/backend/src/gitlab.test.ts
+++ b/packages/backend/src/gitlab.test.ts
@@ -1,6 +1,6 @@
-import { expect, test } from 'vitest';
-import { shouldExcludeProject } from './gitlab';
-import { ProjectSchema } from '@gitbeaker/rest';
+import { expect, test, vi } from 'vitest';
+import { getGitLabProjectsForGroupTree, shouldExcludeProject } from './gitlab';
+import { Gitlab, GroupSchema, ProjectSchema } from '@gitbeaker/rest';
 
 
 test('shouldExcludeProject returns false when the project is not excluded.', () => {
@@ -154,3 +154,129 @@ test('shouldExcludeProject include.topics matching is case-sensitive on the proj
         include: { topics: ['backend'] },
     })).toBe(true);
 });
+
+test('getGitLabProjectsForGroupTree walks paginated subgroup trees without includeSubgroups queries.', async () => {
+    const rootProjectPage1 = {
+        id: 1,
+        path_with_namespace: 'root/project-a',
+    } as ProjectSchema;
+    const rootProjectPage2 = {
+        id: 2,
+        path_with_namespace: 'root/project-b',
+    } as ProjectSchema;
+    const childProject = {
+        id: 3,
+        path_with_namespace: 'root/child/project-c',
+    } as ProjectSchema;
+    const grandchildProject = {
+        id: 4,
+        path_with_namespace: 'root/child/grandchild/project-d',
+    } as ProjectSchema;
+
+    const projectsByGroupPage = new Map<string, ProjectSchema[]>([
+        ['root:1', [rootProjectPage1]],
+        ['root:2', [rootProjectPage2]],
+        ['root/child:1', [childProject]],
+        ['root/child/grandchild:1', [grandchildProject]],
+    ]);
+
+    const subgroupsByGroupPage = new Map<string, GroupSchema[]>([
+        ['root:1', [
+            {
+                id: 10,
+                full_path: 'root/child',
+            } as GroupSchema,
+        ]],
+        ['root:2', [
+            {
+                id: 11,
+                full_path: 'root/other-child',
+            } as GroupSchema,
+        ]],
+        ['root/child:1', [
+            {
+                id: 12,
+                full_path: 'root/child/grandchild',
+            } as GroupSchema,
+        ]],
+    ]);
+
+    const api = {
+        Groups: {
+            allProjects: vi.fn(async (group: string | number, options: { page: number }) => ({
+                data: projectsByGroupPage.get(`${group}:${options.page}`) ?? [],
+                paginationInfo: {
+                    next: group === 'root' && options.page === 1 ? 2 : null,
+                },
+            })),
+            allSubgroups: vi.fn(async (group: string | number, options: { page: number }) => ({
+                data: subgroupsByGroupPage.get(`${group}:${options.page}`) ?? [],
+                paginationInfo: {
+                    next: group === 'root' && options.page === 1 ? 2 : null,
+                },
+            })),
+        },
+    } as unknown as InstanceType<typeof Gitlab>;
+
+    const projects = await getGitLabProjectsForGroupTree(api, 'root');
+
+    expect(projects.map(project => project.path_with_namespace)).toEqual([
+        'root/project-a',
+        'root/project-b',
+        'root/child/project-c',
+        'root/child/grandchild/project-d',
+    ]);
+
+    expect(api.Groups.allProjects).toHaveBeenCalledWith('root', expect.objectContaining({
+        page: 1,
+        perPage: 100,
+        pagination: 'offset',
+        showExpanded: true,
+        includeSubgroups: false,
+    }));
+    expect(api.Groups.allProjects).toHaveBeenCalledWith('root', expect.objectContaining({
+        page: 2,
+        includeSubgroups: false,
+    }));
+    expect(api.Groups.allProjects).toHaveBeenCalledWith('root/child', expect.objectContaining({
+        includeSubgroups: false,
+    }));
+    expect(api.Groups.allProjects).toHaveBeenCalledWith('root/child/grandchild', expect.objectContaining({
+        includeSubgroups: false,
+    }));
+    expect(api.Groups.allProjects).toHaveBeenCalledWith('root/other-child', expect.objectContaining({
+        includeSubgroups: false,
+    }));
+    expect(api.Groups.allProjects).not.toHaveBeenCalledWith(expect.anything(), expect.objectContaining({
+        includeSubgroups: true,
+    }));
+});
+
+test('getGitLabProjectsForGroupTree stops when GitLab returns a non-advancing next page.', async () => {
+    const project = {
+        id: 1,
+        path_with_namespace: 'root/project-a',
+    } as ProjectSchema;
+
+    const api = {
+        Groups: {
+            allProjects: vi.fn(async () => ({
+                data: [project],
+                paginationInfo: {
+                    next: 1,
+                },
+            })),
+            allSubgroups: vi.fn(async () => ({
+                data: [],
+                paginationInfo: {
+                    next: null,
+                },
+            })),
+        },
+    } as unknown as InstanceType<typeof Gitlab>;
+
+    const projects = await getGitLabProjectsForGroupTree(api, 'root');
+
+    expect(projects).toEqual([project]);
+    expect(api.Groups.allProjects).toHaveBeenCalledTimes(1);
+});
diff --git a/packages/backend/src/gitlab.ts b/packages/backend/src/gitlab.ts
index 94a6e0710..13de8f2c3 100644
--- a/packages/backend/src/gitlab.ts
+++ b/packages/backend/src/gitlab.ts
@@ -1,4 +1,4 @@
-import { Gitlab, ProjectSchema } from "@gitbeaker/rest";
+import { Gitlab, GroupSchema, ProjectSchema } from "@gitbeaker/rest";
 import * as Sentry from "@sentry/node";
 import { getTokenFromConfig } from "@sourcebot/shared";
 import { createLogger } from "@sourcebot/shared";
@@ -10,6 +10,100 @@ import { fetchWithRetry, measure } from "./utils.js";
 
 const logger = createLogger('gitlab');
 export const GITLAB_CLOUD_HOSTNAME = "gitlab.com";
+const GITLAB_PAGE_SIZE = 100;
+
+type GitLabApi = InstanceType<typeof Gitlab>;
+
+type GitLabPaginatedResponse<T> = {
+    data: T[];
+    paginationInfo?: {
+        next: number | null;
+    };
+};
+
+const fetchAllGitLabPages = async <T>(
+    identifier: string,
+    fetchPage: (page: number) => Promise<GitLabPaginatedResponse<T>>,
+): Promise<T[]> => {
+    const items: T[] = [];
+    let page = 1;
+
+    while (true) {
+        const response = await fetchWithRetry(
+            () => fetchPage(page),
+            `${identifier} page ${page}`,
+            logger,
+        );
+
+        items.push(...response.data);
+
+        const nextPage = response.paginationInfo?.next;
+        if (!nextPage) {
+            break;
+        }
+        if (nextPage <= page) {
+            logger.warn(`Stopping pagination for ${identifier}: GitLab returned non-advancing next page ${nextPage} after page ${page}.`);
+            break;
+        }
+
+        page = nextPage;
+    }
+
+    return items;
+};
+
+export const getGitLabProjectsForGroupTree = async (
+    api: GitLabApi,
+    rootGroup: string,
+): Promise<ProjectSchema[]> => {
+    const projectsById = new Map<number, ProjectSchema>();
+    const groupsToVisit: Array<string | number> = [rootGroup];
+    let groupIndex = 0;
+    const visitedGroups = new Set<string>();
+
+    while (groupIndex < groupsToVisit.length) {
+        const group = groupsToVisit[groupIndex++]!;
+        const groupKey = String(group);
+        if (visitedGroups.has(groupKey)) {
+            continue;
+        }
+        visitedGroups.add(groupKey);
+
+        const [projects, subgroups] = await Promise.all([
+            fetchAllGitLabPages<ProjectSchema>(
+                `projects for GitLab group ${groupKey}`,
+                async (page) => api.Groups.allProjects(group, {
+                    perPage: GITLAB_PAGE_SIZE,
+                    page,
+                    pagination: 'offset',
+                    showExpanded: true,
+                    includeSubgroups: false,
+                }) as Promise<GitLabPaginatedResponse<ProjectSchema>>,
+            ),
+            fetchAllGitLabPages<GroupSchema>(
+                `subgroups for GitLab group ${groupKey}`,
+                async (page) => api.Groups.allSubgroups(group, {
+                    perPage: GITLAB_PAGE_SIZE,
+                    page,
+                    pagination: 'offset',
+                    showExpanded: true,
+                }) as Promise<GitLabPaginatedResponse<GroupSchema>>,
+            ),
+        ]);
+
+        for (const project of projects) {
+            projectsById.set(project.id, project);
+        }
+
+        for (const subgroup of subgroups) {
+            groupsToVisit.push(subgroup.full_path ?? subgroup.id);
+        }
+    }
+
+    logger.debug(`Fetched ${projectsById.size} projects across ${visitedGroups.size} GitLab group(s) under ${rootGroup}.`);
+
+    return [...projectsById.values()];
+};
 
 export const createGitLabFromPersonalAccessToken = async ({ token, url }: { token?: string, url?: string }) => {
     const isGitLabCloud = url ? new URL(url).hostname === GITLAB_CLOUD_HOSTNAME : true;
@@ -81,11 +175,7 @@ export const getGitLabReposFromConfig = async (config: GitlabConnectionConfig) =
             try {
                 logger.debug(`Fetching project info for group ${group}...`);
                 const { durationMs, data } = await measure(async () => {
-                    const fetchFn = () => api.Groups.allProjects(group, {
-                        perPage: 100,
-                        includeSubgroups: true
-                    });
-                    return fetchWithRetry(fetchFn, `group ${group}`, logger);
+                    return getGitLabProjectsForGroupTree(api, group);
                 });
                 logger.debug(`Found ${data.length} projects in group ${group} in ${durationMs}ms.`);
                 return {
@@ -333,4 +423,4 @@ export const getOAuthScopesForAuthenticatedUser = async (api: InstanceType<typeo
         logger.error('Failed to fetch OAuth scopes for authenticated user.', error);
         throw error;
     }
-}
\ No newline at end of file
+}