diff --git a/packages/indexer-api/src/controllers/balances.ts b/packages/indexer-api/src/controllers/balances.ts
index 2699c6d1..5001304c 100644
--- a/packages/indexer-api/src/controllers/balances.ts
+++ b/packages/indexer-api/src/controllers/balances.ts
@@ -22,11 +22,16 @@ export class BalancesController {
   };
 
   public getSpokePoolBalance = (
-    req: Request,
+    { query }: Request,
     res: Response,
     next: NextFunction,
   ) => {
-    req.query && s.assert(req.query, SpokePoolBalanceParams);
-    res.json([]);
+    if (!s.is(query, SpokePoolBalanceParams)) {
+      return res.status(400).json({ error: "Invalid query" });
+    }
+    this.service
+      .spokePoolBalance(query)
+      .then((result) => res.json(result))
+      .catch((err) => next(err));
   };
 }
diff --git a/packages/indexer-api/src/dtos/balances.dto.ts b/packages/indexer-api/src/dtos/balances.dto.ts
index 3c6efa00..6237913f 100644
--- a/packages/indexer-api/src/dtos/balances.dto.ts
+++ b/packages/indexer-api/src/dtos/balances.dto.ts
@@ -8,8 +8,19 @@ export const HubPoolBalanceQueryParams = s.object({
 // query spokepools by chainId, must specify
 export const SpokePoolBalanceParams = s.object({
   chainId: s.number(),
+  l1Token: s.optional(s.string()),
   // unsure why we have timestamp, implies we are storign history of balances? this is in the spec.
   timestamp: s.number(),
-  // unsure why specified as l2Token in spec, don't we have spoke pool on L1?
-  l2Token: s.optional(s.number()),
 });
+
+export type SpokePoolBalanceResultElement = {
+  lastExecutedRunningBalance: string;
+  pendingRunningBalance: string | null;
+  pendingNetSendAmount: string | null;
+  currentRunningBalance: string;
+  currentNetSendAmount: string;
+};
+
+export type SpokePoolBalanceResults = {
+  [chainId: string]: SpokePoolBalanceResultElement;
+};
diff --git a/packages/indexer-api/src/services/balances.ts b/packages/indexer-api/src/services/balances.ts
index 0d0b962c..e5dfa739 100644
--- a/packages/indexer-api/src/services/balances.ts
+++ b/packages/indexer-api/src/services/balances.ts
@@ -1,15 +1,31 @@
 import assert from "assert";
 import Redis from "ioredis";
 import * as Indexer from "@repo/indexer";
+import {
+  SpokePoolBalanceResultElement,
+  SpokePoolBalanceResults,
+} from "../dtos/balances.dto";
 
 export class BalancesService {
   hubBalancesCache: Indexer.redis.hubBalancesCache.HubPoolBalanceCache;
-  constructor(private redis: Redis) {
+  currentBundleLeavesCache: Indexer.redis.bundleLeavesCache.BundleLeavesCache;
+  proposedBundleLeavesCache: Indexer.redis.bundleLeavesCache.BundleLeavesCache;
+  constructor(redis: Redis) {
     this.hubBalancesCache =
       new Indexer.redis.hubBalancesCache.HubPoolBalanceCache({
         redis,
         prefix: "hubBalanceCache",
       });
+    this.currentBundleLeavesCache =
+      new Indexer.redis.bundleLeavesCache.BundleLeavesCache({
+        redis,
+        prefix: "currentBundleCache",
+      });
+    this.proposedBundleLeavesCache =
+      new Indexer.redis.bundleLeavesCache.BundleLeavesCache({
+        redis,
+        prefix: "proposedBundleCache",
+      });
   }
   async hubPoolBalance(params?: {
     l1Token?: string;
@@ -22,4 +38,71 @@ export class BalancesService {
       return this.hubBalancesCache.getAllL1Tokens();
     }
   }
+
+  async spokePoolBalance(params: {
+    chainId: number;
+    l1Token?: string;
+  }): Promise<SpokePoolBalanceResults> {
+    const { l1Token, chainId } = params;
+    const bundleLeaves = await resolveAllL1Tokens(
+      l1Token,
+      chainId,
+      this.proposedBundleLeavesCache,
+      this.currentBundleLeavesCache,
+    );
+    return bundleLeaves.reduce(
+      (acc, bundleLeaf) => ({
+        ...acc,
+        [bundleLeaf.chainId]: {
+          lastExecutedRunningBalance: bundleLeaf.lastExecutedRunningBalance,
+          pendingRunningBalance: bundleLeaf.pendingRunningBalance,
+          pendingNetSendAmount: bundleLeaf.pendingNetSendAmount,
+          currentRunningBalance: bundleLeaf.currentRunningBalance,
+          currentNetSendAmount: bundleLeaf.currentNetSendAmount,
+        },
+      }),
+      {} as SpokePoolBalanceResults,
+    );
+  }
+}
+
+function combineBundleLeaf(
+  proposedBundleLeaf?: Indexer.redis.bundleLeavesCache.BundleLeaf,
+  currentBundleLeaf?: Indexer.redis.bundleLeavesCache.BundleLeaf,
+): SpokePoolBalanceResultElement & { chainId: number } {
+  assert(currentBundleLeaf, "currentBundleLeaf is required");
+  return {
+    chainId: currentBundleLeaf.chainId,
+    lastExecutedRunningBalance: currentBundleLeaf.lastExecutedRunningBalance,
+    pendingRunningBalance: proposedBundleLeaf?.runningBalance ?? null,
+    pendingNetSendAmount: proposedBundleLeaf?.netSendAmount ?? null,
+    currentRunningBalance: currentBundleLeaf.runningBalance,
+    currentNetSendAmount: currentBundleLeaf.netSendAmount,
+  };
+}
+
+async function resolveAllL1Tokens(
+  l1Token: string | undefined,
+  chainId: number,
+  proposedCache: Indexer.redis.bundleLeavesCache.BundleLeavesCache,
+  currentCache: Indexer.redis.bundleLeavesCache.BundleLeavesCache,
+): Promise<(SpokePoolBalanceResultElement & { chainId: number })[]> {
+  if (l1Token) {
+    const currentL1Cache = await currentCache.get(chainId, l1Token);
+    const proposedL1Cache = await proposedCache.get(chainId, l1Token);
+    return [combineBundleLeaf(proposedL1Cache, currentL1Cache)];
+  } else {
+    const currentL1Cache = await currentCache.getByChainId(chainId);
+    return Promise.all(
+      currentL1Cache
+        .filter((v) => v !== undefined)
+        .map(async (currentCacheValue) => {
+          const proposedCacheValue = await proposedCache.get(
+            currentCacheValue.chainId,
+            currentCacheValue.l1Token,
+          );
+          return combineBundleLeaf(proposedCacheValue, currentCacheValue);
+        }),
+    );
+  }
 }
diff --git a/packages/indexer/src/redis/bundleLeavesCache.ts b/packages/indexer/src/redis/bundleLeavesCache.ts
index 2bde9dc8..e570217c 100644
--- a/packages/indexer/src/redis/bundleLeavesCache.ts
+++ b/packages/indexer/src/redis/bundleLeavesCache.ts
@@ -11,6 +11,7 @@ export const BundleLeaf = s.object({
   l1Token: s.string(),
   netSendAmount: s.string(),
   runningBalance: s.string(),
+  lastExecutedRunningBalance: s.string(),
 });
 export type BundleLeaf = s.Infer<typeof BundleLeaf>;
 export type BundleLeaves = BundleLeaf[];
diff --git a/packages/indexer/src/services/BundleBuilderService.ts b/packages/indexer/src/services/BundleBuilderService.ts
index 98ccd3a9..b7c62756 100644
--- a/packages/indexer/src/services/BundleBuilderService.ts
+++ b/packages/indexer/src/services/BundleBuilderService.ts
@@ -245,11 +245,22 @@ export class BundleBuilderService extends BaseIndexer {
       // and not any specific proposal
       convertProposalRangeResultToProposalRange(ranges),
     );
+
     // first clear the cache to prepare for update
     await this.currentBundleCache.clear();
     // Persist this to Redis
     await Promise.all(
       resultsToPersist.flatMap((leaf) => {
+        const lastExecutedRunningBalance =
+          lastExecutedBundle.proposal.bundleEvaluationBlockNumbers[
+            lastExecutedBundle.proposal.chainIds.findIndex(
+              (chainId) => leaf.chainId === chainId,
+            )
+          ];
+        assert(
+          lastExecutedRunningBalance,
+          "Last executed running balance not found",
+        );
         assert(
           leaf.l1Tokens.length == leaf.netSendAmounts.length,
           "Net send amount count does not match token counts",
@@ -264,6 +275,7 @@ export class BundleBuilderService extends BaseIndexer {
             l1Token,
             netSendAmount: leaf.netSendAmounts[tokenIndex]!,
             runningBalance: leaf.runningBalances[tokenIndex]!,
+            lastExecutedRunningBalance: String(lastExecutedRunningBalance),
           });
         });
       }),
@@ -309,6 +321,16 @@ export class BundleBuilderService extends BaseIndexer {
     // Persist this to Redis
     await Promise.all(
       resultsToPersist.flatMap((leaf) => {
+        const lastExecutedRunningBalance =
+          lastExecutedBundle.proposal.bundleEvaluationBlockNumbers[
+            lastExecutedBundle.proposal.chainIds.findIndex(
+              (chainId) => leaf.chainId === chainId,
+            )
+          ];
+        assert(
+          lastExecutedRunningBalance,
+          "Last executed running balance not found",
+        );
         assert(
           leaf.l1Tokens.length == leaf.netSendAmounts.length,
           "Net send amount count does not match token counts",
@@ -323,6 +345,7 @@ export class BundleBuilderService extends BaseIndexer {
             l1Token,
             netSendAmount: leaf.netSendAmounts[tokenIndex]!,
             runningBalance: leaf.runningBalances[tokenIndex]!,
+            lastExecutedRunningBalance: String(lastExecutedRunningBalance),
           });
         });
       }),