diff --git a/zp-relayer/pool/RelayPool.ts b/zp-relayer/pool/RelayPool.ts
index 8907b8c..ef5d53b 100644
--- a/zp-relayer/pool/RelayPool.ts
+++ b/zp-relayer/pool/RelayPool.ts
@@ -250,18 +250,12 @@ export class RelayPool extends BasePool<Network> {
   }
 
   async onSend({ outCommit, nullifier, memo, commitIndex }: ProcessResult<RelayPool>, txHash: string): Promise<void> {
-    const prefixedMemo = buildPrefixedMemo(
-      outCommit,
-      txHash,
-      memo
-    )
-
-    await this.txStore.add(commitIndex, prefixedMemo)
-
     if (nullifier) {
       logger.debug('Adding nullifier %s to OS', nullifier)
       await this.optimisticState.nullifiers.add([nullifier])
     }
+
+    await this.cacheTxLocally(commitIndex, outCommit, txHash, memo);
   }
 
   async onConfirmed(res: ProcessResult<RelayPool>, txHash: string, callback?: () => Promise<void>, jobId?: string): Promise<void> {
@@ -274,10 +268,23 @@ export class RelayPool extends BasePool<Network> {
         poolJob.data.transaction.state = JobState.COMPLETED;
         poolJob.data.transaction.txHash = txHash;
         await poolJob.update(poolJob.data);
+
+        await this.cacheTxLocally(res.commitIndex, res.outCommit, txHash, res.memo);
       }
     }
   }
 
+  protected async cacheTxLocally(index: number, commit: string, txHash: string, memo: string) {
+    // store or updating local tx store
+    // (we should keep sent transaction until the indexer grab them)
+    const prefixedMemo = buildPrefixedMemo(
+      commit,
+      txHash,
+      memo
+    );
+    await this.txStore.add(index, prefixedMemo);
+  }
+
   async getIndexerInfo() {
     const info = await fetchJson(this.indexerUrl, '/info', [])
     return info
diff --git a/zp-relayer/services/relayer/endpoints.ts b/zp-relayer/services/relayer/endpoints.ts
index 36ca754..6f6a650 100644
--- a/zp-relayer/services/relayer/endpoints.ts
+++ b/zp-relayer/services/relayer/endpoints.ts
@@ -187,6 +187,19 @@ async function relayerInfo(req: Request, res: Response, { pool }: PoolInjection)
   }
   const info = await response.json()
 
+  const indexerMaxIdx = Math.max(parseInt(info.deltaIndex ?? '0'), parseInt(info.optimisticDeltaIndex ?? '0'))
+
+  const txStore = (pool as RelayPool).txStore
+  const pendingCnt = await txStore.getAll()
+    .then(keys => {
+      return Object.entries(keys)
+        .map(([i]) => parseInt(i) as number)
+        .filter(i => indexerMaxIdx <= i)
+    })
+    .then(a => a.length);
+
+    info.pendingDeltaIndex = indexerMaxIdx + pendingCnt * OUTPLUSONE;
+
   res.json(info)
 }