diff --git a/src/lib/flows/wave/add-issues-to-wave-program/configure-details.svelte b/src/lib/flows/wave/add-issues-to-wave-program/configure-details.svelte
index ca070e1d0..ccd050318 100644
--- a/src/lib/flows/wave/add-issues-to-wave-program/configure-details.svelte
+++ b/src/lib/flows/wave/add-issues-to-wave-program/configure-details.svelte
@@ -14,14 +14,13 @@
   import Card from '$lib/components/wave/card/card.svelte';
   import ListSelect from '$lib/components/list-select/list-select.svelte';
   import type { Items } from '$lib/components/list-select/list-select.types';
-  import { addIssueToWaveProgram } from '$lib/utils/wave/wavePrograms';
+  import { addIssuesToWaveProgram, BULK_ADD_MAX_ISSUES } from '$lib/utils/wave/wavePrograms';
   import { invalidate } from '$app/navigation';
   import { notifyIssuesUpdated } from '$lib/components/wave/issues-page/issue-update-coordinator';
   import AnnotationBox from '$lib/components/annotation-box/annotation-box.svelte';
   import { getIssue } from '$lib/utils/wave/issues';
   import { getPointsForComplexity } from '$lib/utils/wave/get-points-for-complexity';
   import extractApiErrorMessage from '$lib/utils/wave/utils/extract-api-error-message';
-  import mapWithConcurrency from '$lib/utils/map-with-concurrency';
   import { SvelteMap, SvelteSet } from 'svelte/reactivity';
 
   const dispatch = createEventDispatcher<StepComponentEvents>();
@@ -300,17 +299,40 @@
         const selectedWaveId = selectedWaveIds[0];
         const issuesToAdd = submittableIssues;
 
-        // Adds sequentialize on an org-wide lock on the backend, so firing them
-        // all at once just piles up lock waiters. Keep concurrency low.
-        const results = await mapWithConcurrency(
-          issuesToAdd,
-          (issue) => addIssueToWaveProgram(undefined, selectedWaveId, issue.id, activeComplexity),
-          2,
-        );
+        // One bulk request per chunk of BULK_ADD_MAX_ISSUES, sequentially. The
+        // backend adds each chunk in a single transaction with one org-lock
+        // acquisition, reporting per-issue outcomes — unlike parallel single
+        // adds, which serialize on that lock and can time out (wave#735).
+        const resultByIssueId = new SvelteMap<string, { success: boolean; error: string | null }>();
+        for (let i = 0; i < issuesToAdd.length; i += BULK_ADD_MAX_ISSUES) {
+          const chunk = issuesToAdd.slice(i, i + BULK_ADD_MAX_ISSUES);
+          try {
+            const response = await addIssuesToWaveProgram(
+              undefined,
+              selectedWaveId,
+              chunk.map((issue) => ({ issueId: issue.id, complexity: activeComplexity })),
+            );
+            for (const result of response.results) {
+              resultByIssueId.set(result.issueId, result);
+            }
+          } catch (error) {
+            // Whole-chunk failure (network, 5xx, batch-level 4xx): report every
+            // issue in the chunk as failed but keep going — later chunks may
+            // succeed, and earlier ones already have.
+            for (const issue of chunk) {
+              resultByIssueId.set(issue.id, {
+                success: false,
+                error: extractApiErrorMessage(error),
+              });
+            }
+          }
+        }
 
         // Refresh every issue that was added successfully — even on partial
         // failure — so the list reflects reality regardless of the outcome.
-        const succeededIssues = issuesToAdd.filter((_, i) => results[i].status === 'fulfilled');
+        const succeededIssues = issuesToAdd.filter(
+          (issue) => resultByIssueId.get(issue.id)?.success,
+        );
         if (succeededIssues.length > 0) {
           const updatedIssues = (
             await Promise.all(succeededIssues.map((issue) => getIssue(undefined, issue.id)))
@@ -321,12 +343,11 @@
         }
 
         const failures = issuesToAdd
-          .map((issue, i) => ({ issue, result: results[i] }))
-          .filter(
-            (entry): entry is { issue: IssueDetailsDto; result: PromiseRejectedResult } =>
-              entry.result.status === 'rejected',
-          )
-          .map(({ issue, result }) => ({ issue, reason: result.reason }));
+          .filter((issue) => !resultByIssueId.get(issue.id)?.success)
+          .map((issue) => ({
+            issue,
+            reason: resultByIssueId.get(issue.id)?.error ?? 'Unknown error',
+          }));
 
         if (failures.length > 0) {
           throw new Error(formatAddIssueFailures(failures, issuesToAdd.length));
diff --git a/src/lib/utils/wave/types/waveProgram.ts b/src/lib/utils/wave/types/waveProgram.ts
index ccbcaf169..2caa1e1c1 100644
--- a/src/lib/utils/wave/types/waveProgram.ts
+++ b/src/lib/utils/wave/types/waveProgram.ts
@@ -367,6 +367,23 @@ export const waveProgramIssueWithDetailsDtoSchema = z.object({
   removedBy: waveUserDtoSchema.nullable(),
 });
 
+export const bulkAddIssueResultDtoSchema = z.object({
+  issueId: z.uuid(),
+  success: z.boolean(),
+  waveProgramIssue: waveProgramIssueWithDetailsDtoSchema.nullable(),
+  error: z.string().nullable(),
+});
+export type BulkAddIssueResultDto = z.infer<typeof bulkAddIssueResultDtoSchema>;
+
+export const bulkAddIssuesToWaveProgramResponseDtoSchema = z.object({
+  results: z.array(bulkAddIssueResultDtoSchema),
+  addedCount: z.number().int(),
+  failedCount: z.number().int(),
+});
+export type BulkAddIssuesToWaveProgramResponseDto = z.infer<
+  typeof bulkAddIssuesToWaveProgramResponseDtoSchema
+>;
+
 // ===========================
 // Wave Types
 // ===========================
diff --git a/src/lib/utils/wave/wavePrograms.ts b/src/lib/utils/wave/wavePrograms.ts
index c9a73f068..64d788172 100644
--- a/src/lib/utils/wave/wavePrograms.ts
+++ b/src/lib/utils/wave/wavePrograms.ts
@@ -7,6 +7,7 @@ import {
 } from './types/pagination';
 import {
   batchApplyResponseSchema,
+  bulkAddIssuesToWaveProgramResponseDtoSchema,
   repoAppealContextDtoSchema,
   repoRejectionAppealDtoSchema,
   waveProgramApplicationLimitsDtoSchema,
@@ -251,6 +252,37 @@ export async function addIssueToWaveProgram(
   );
 }
 
+/**
+ * Server-side cap on issues per bulk-add request (mirrors `BULK_ADD_MAX_ISSUES`
+ * in the Wave API). Larger selections must be chunked by the caller.
+ */
+export const BULK_ADD_MAX_ISSUES = 50;
+
+/**
+ * Adds up to `BULK_ADD_MAX_ISSUES` issues to a wave program in a single request
+ * (and a single backend transaction). Per-issue failures are reported in the
+ * response's `results` without failing the batch. Prefer this over parallel
+ * `addIssueToWaveProgram` calls: those serialize on a per-org lock server-side
+ * and can time out in bulk (see wave#735).
+ */
+export async function addIssuesToWaveProgram(
+  f = fetch,
+  waveProgramId: string,
+  issues: { issueId: string; complexity?: Complexity }[],
+) {
+  if (issues.length > BULK_ADD_MAX_ISSUES) {
+    throw new Error(`Cannot add more than ${BULK_ADD_MAX_ISSUES} issues per request`);
+  }
+
+  return parseRes(
+    bulkAddIssuesToWaveProgramResponseDtoSchema,
+    await authenticatedCall(f, `/api/wave-programs/${waveProgramId}/issues/bulk`, {
+      method: 'POST',
+      body: JSON.stringify({ issues }),
+    }),
+  );
+}
+
 export async function removeIssueFromWaveProgram(
   f = fetch,
   waveProgramId: string,