diff --git a/frontend/src/lib/components/GitHubAppIntegration.svelte b/frontend/src/lib/components/GitHubAppIntegration.svelte
index 7aa136b072..11844d7d9c 100644
--- a/frontend/src/lib/components/GitHubAppIntegration.svelte
+++ b/frontend/src/lib/components/GitHubAppIntegration.svelte
@@ -55,6 +55,19 @@
 			)
 	)
 
+	// Org names that appear on more than one installation, so the dropdown can
+	// tell those entries apart.
+	let duplicatedAccountIds = $derived(
+		new Set(
+			githubState.workspaceGithubInstallations
+				.filter(
+					(installation, _, array) =>
+						array.filter((other) => other.account_id === installation.account_id).length > 1
+				)
+				.map((installation) => installation.account_id)
+		)
+	)
+
 	let showGitHubApp = $derived(
 		resourceType === 'git_repository' &&
 			$workspaceStore &&
@@ -205,29 +218,47 @@
 								<div class="flex flex-row gap-2 w-full">
 									<div class="flex flex-col gap-1 flex-1">
 										<p class="text-sm font-semibold text-secondary">GitHub Account ID</p>
-										<select bind:value={githubState.selectedGHAppAccountId}>
-											<option value="" disabled>Select GitHub Account ID</option>
+										<select
+											bind:value={githubState.selectedGHAppInstallationId}
+											onchange={() => (githubState.selectedGHAppRepository = undefined)}
+										>
+											<option value={undefined} disabled>Select GitHub Account ID</option>
 											{#each githubState.workspaceGithubInstallations as installation (`select-${installation.installation_id}-${installation.workspace_id}`)}
-												<option value={installation.account_id} disabled={!!installation.error}>
-													{installation.account_id}{installation.error ? ' (token error)' : ''}
+												{@const details = [
+													duplicatedAccountIds.has(installation.account_id)
+														? `${installation.installation_id}`
+														: undefined,
+													installation.error ? 'token error' : undefined
+												].filter(Boolean)}
+												<option
+													value={installation.installation_id}
+													disabled={!!installation.error}
+												>
+													{installation.account_id}{details.length
+														? ` (${details.join(', ')})`
+														: ''}
 												</option>
 											{/each}
 										</select>
 									</div>
-									{#if githubState.selectedGHAppAccountId}
+									{#if githubState.selectedGHAppInstallationId !== undefined}
 										{@const selectedInstallation = githubState.workspaceGithubInstallations.find(
-											(inst) => inst.account_id === githubState.selectedGHAppAccountId
+											(inst) => inst.installation_id === githubState.selectedGHAppInstallationId
 										)}
 										{#if selectedInstallation}
 											<div class="flex flex-col gap-1 flex-1">
 												<p class="text-sm font-semibold text-secondary">Repository</p>
-												<RepositorySelector
-													bind:selectedRepository={githubState.selectedGHAppRepository}
-													accountId={githubState.selectedGHAppAccountId}
-													initialRepositories={selectedInstallation.repositories}
-													totalCount={selectedInstallation.total_count}
-													perPage={selectedInstallation.per_page}
-												/>
+												<!-- RepositorySelector snapshots its repositories and page cursor at
+												     mount, so switching installation has to remount it. -->
+												{#key selectedInstallation.installation_id}
+													<RepositorySelector
+														bind:selectedRepository={githubState.selectedGHAppRepository}
+														installationId={selectedInstallation.installation_id}
+														initialRepositories={selectedInstallation.repositories}
+														totalCount={selectedInstallation.total_count}
+														perPage={selectedInstallation.per_page}
+													/>
+												{/key}
 											</div>
 										{/if}
 									{/if}
diff --git a/frontend/src/lib/components/RepositorySelector.svelte b/frontend/src/lib/components/RepositorySelector.svelte
index cfeaa3945d..30f8361cbb 100644
--- a/frontend/src/lib/components/RepositorySelector.svelte
+++ b/frontend/src/lib/components/RepositorySelector.svelte
@@ -11,7 +11,7 @@
 	interface Props {
 		disabled?: boolean
 		selectedRepository?: string | undefined
-		accountId: string
+		installationId: number
 		initialRepositories: Repository[]
 		totalCount: number
 		perPage: number
@@ -23,7 +23,7 @@
 	let {
 		disabled = false,
 		selectedRepository = $bindable(),
-		accountId,
+		installationId,
 		initialRepositories,
 		totalCount,
 		perPage,
@@ -67,8 +67,8 @@
 				page: nextPage
 			})
 
-			// Find the matching installation and get its repositories
-			const installation = installations.find((inst) => inst.account_id === accountId)
+			// Match on installation_id: several installations can share one account_id
+			const installation = installations.find((inst) => inst.installation_id === installationId)
 
 			if (installation?.repositories) {
 				// Append new repos to existing ones
@@ -95,8 +95,8 @@
 				}))}
 				placeholder="Select repository..."
 				clearable
-				disabled={disabled}
-				bind:filterText={filterText}
+				{disabled}
+				bind:filterText
 				bind:value={selectedRepository}
 			/>
 			{#if hasMoreRepos}
diff --git a/frontend/src/lib/githubApp.ts b/frontend/src/lib/githubApp.ts
index f60b1f8538..666734546e 100644
--- a/frontend/src/lib/githubApp.ts
+++ b/frontend/src/lib/githubApp.ts
@@ -10,7 +10,12 @@ export interface GitHubAppState {
 	loadingGithubInstallations: boolean
 	githubInstallations: GetGlobalConnectedRepositoriesResponse
 	workspaceGithubInstallations: GetGlobalConnectedRepositoriesResponse
-	selectedGHAppAccountId: string | undefined
+	/**
+	 * Installations are keyed by `installation_id`, never by `account_id`: an org
+	 * can be installed more than once (re-installed, or added from another
+	 * workspace), and matching on the org name resolves to the wrong one.
+	 */
+	selectedGHAppInstallationId: number | undefined
 	selectedGHAppRepository: string | undefined
 	githubInstallationUrl: string | undefined
 	installationCheckInterval: number | undefined
@@ -25,11 +30,6 @@ export interface GitHubAppState {
 	isGhesSelfManaged: boolean
 }
 
-export interface GitHubRepository {
-	name: string
-	url: string
-}
-
 export interface GitHubAppError extends Error {
 	code: 'VALIDATION_ERROR' | 'NETWORK_ERROR' | 'AUTH_ERROR' | 'UNKNOWN_ERROR'
 	details?: unknown
@@ -101,7 +101,7 @@ export function createGitHubAppState(): GitHubAppState {
 		loadingGithubInstallations: false,
 		githubInstallations: [],
 		workspaceGithubInstallations: [],
-		selectedGHAppAccountId: undefined,
+		selectedGHAppInstallationId: undefined,
 		selectedGHAppRepository: undefined,
 		githubInstallationUrl: undefined,
 		installationCheckInterval: undefined,
@@ -241,18 +241,6 @@ export function stopInstallationCheck(state: GitHubAppState): void {
 	state.isCheckingInstallation = false
 }
 
-/**
- * Gets repositories for a specific GitHub account
- */
-export function getRepositories(state: GitHubAppState, accountId: string): GitHubRepository[] {
-	if (!accountId) return []
-
-	return (
-		state.githubInstallations.find((installation) => installation.account_id === accountId)
-			?.repositories || []
-	)
-}
-
 /**
  * Adds a GitHub installation to the current workspace
  */