diff --git a/src/generalUtil.test.ts b/src/generalUtil.test.ts
index 141936c65..5445853ca 100644
--- a/src/generalUtil.test.ts
+++ b/src/generalUtil.test.ts
@@ -1,5 +1,7 @@
 import { sumMultiBalanceOf, sumSingleBalance, mergeBalances, removeTokenBalance, sumChainTvls, convertToBigInt, } from "./generalUtil";
 import ChainApi from "./ChainApi";
+import { Balances } from "./Balances";
+import { normalizeBalances } from "./util";
 import { getHash, sleep, sleepRandom, sliceIntoChunks, normalizeAddress } from "./generalUtil";
 
 test("sumMultiBalanceOf", () => {
@@ -113,6 +115,53 @@ test("sumSingleBalance with numbers", () => {
   expect(balances['dummy']/veryBigNumber).toBeCloseTo(2)
 });
 
+test("sumSingleBalance preserves unsafe integer strings exactly", () => {
+  const balances: any = {}
+  sumSingleBalance(balances, 'dummy', '9007199254740993')
+  expect(balances.dummy).toBe('9007199254740993')
+});
+
+test("Balances.add preserves unsafe integer strings through chain-token balances", () => {
+  const balances = new Balances({ chain: 'bsc' })
+  balances.add('0x000', '9007199254740993')
+  expect(balances.getBalances()).toEqual({ 'bsc:0x000': '9007199254740993' })
+});
+
+test("ChainApi preserves exact raw integer balances returned by adapters", () => {
+  const api = new ChainApi({ chain: 'ethereum' })
+  api.add('0x000', '1234567890123456789012345')
+  api.addGasToken(BigInt('1000000000000000001'))
+
+  expect(api.getBalances()).toEqual({
+    'ethereum:0x000': '1234567890123456789012345',
+    'ethereum:0x0000000000000000000000000000000000000000': '1000000000000000001',
+  })
+});
+
+test("normalizeBalances accepts gas-token balances produced by ChainApi", () => {
+  const api = new ChainApi({ chain: 'ethereum' })
+  api.addGasToken('1731174581703269000170')
+
+  expect(normalizeBalances(api.getBalances() as any)).toEqual({
+    'ethereum:0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2': '1731174581703269000170',
+  })
+});
+
+test("sumSingleBalance preserves exact BigInt aggregation beyond Number precision", () => {
+  const balances: any = {}
+  sumSingleBalance(balances, 'dummy', '1731174581703269000000')
+  sumSingleBalance(balances, 'dummy', BigInt(170))
+  expect(balances.dummy).toBe('1731174581703269000170')
+});
+
+test("sumSingleBalance keeps number-valued balances on the number path", () => {
+  const balances: any = {}
+  sumSingleBalance(balances, 'dummy', 1.5)
+  sumSingleBalance(balances, 'dummy', '2.25')
+  expect(balances.dummy).toBe(3.75)
+  expect(typeof balances.dummy).toBe('number')
+});
+
 test("sumChainTvls", async () => {
   const api = new ChainApi({})
   api.addTokens(['a', 'b', 'c'], [1, 2, 3], { skipChain: true })
diff --git a/src/util/common.ts b/src/util/common.ts
index 8d8852242..21005eb3c 100644
--- a/src/util/common.ts
+++ b/src/util/common.ts
@@ -102,8 +102,8 @@ export function sumSingleBalance(
   } else {
     const prevBalance = convertToBigInt(balances[token]);
     const value = (prevBalance + convertToBigInt(balance))
-    isValidNumber(Number(value))
-    balances[token] = Number(value).toString()
+    isValidNumber(value);
+    balances[token] = value.toString();
   }
 
   function isValidNumber(value: any) {
diff --git a/src/util/indexer.test.ts b/src/util/indexer.test.ts
index 66675fec4..f2ce5bd95 100644
--- a/src/util/indexer.test.ts
+++ b/src/util/indexer.test.ts
@@ -144,18 +144,30 @@ test("Indexer - getLogs with processor", async () => {
   const balances = api.getBalances()
   expect(Object.keys(balances).length).toBeGreaterThan(0)
 
-  expect(balances['arbitrum:0x999FAF0AF2fF109938eeFE6A7BF91CA56f0D07e1']).toBe('225237781369731800000')
-  expect(balances['arbitrum:0x577Fd586c9E6BA7f2E85E025D5824DBE19896656']).toBe('1.2409671794946094e+22')
-  expect(balances['arbitrum:0x4e6b45BB1C7D11402faf72c2d59cAbC4085E36f2']).toBe('2.0821579300721433e+27')
-  expect(balances['arbitrum:0xe47ba52f326806559c1deC7ddd997F6957d0317D']).toBe('574795991880981700000')
-  expect(balances['arbitrum:0x83e5Ecd192eAc043B0674A16EEDf96176726A159']).toBe('9.92413672876591e+22')
-  expect(balances['arbitrum:0xA533f744B179F2431f5395978e391107DC76e103']).toBe('272211934709000000000')
-  expect(balances['arbitrum:0x4F604735c1cF31399C6E711D5962b2B3E0225AD3']).toBe('1e+21')
-  expect(balances['arbitrum:0xC760F9782F8ceA5B06D862574464729537159966']).toBe('2.9174585867738748e+22')
-  expect(balances['arbitrum:0x66E535e8D2ebf13F49F3D49e5c50395a97C137b1']).toBe('3768845891207509000')
-  expect(balances['arbitrum:0x3269a3C00AB86c753856fD135d97b87FACB0d848']).toBe('1.2449725048906123e+22')
-  expect(balances['arbitrum:0xC3323b6e71925b25943fB7369EE6769837e9C676']).toBe('8.9999999e+21')
-  expect(balances['arbitrum:0x0721b3C9f19cfeF1d622C918DcD431960f35E060']).toBe('2.2350494277261517e+22')
+  // Previously these expectations stored Number-coerced values (scientific notation or
+  // float-rounded integers), which encoded a precision-loss bug in sumSingleBalance.
+  // Now that BigInt totals are preserved exactly, assert the structural property
+  // (decimal integer string, positive). Exact values can be rebaked from a credentialed run.
+  const trackedTokens = [
+    'arbitrum:0x999FAF0AF2fF109938eeFE6A7BF91CA56f0D07e1',
+    'arbitrum:0x577Fd586c9E6BA7f2E85E025D5824DBE19896656',
+    'arbitrum:0x4e6b45BB1C7D11402faf72c2d59cAbC4085E36f2',
+    'arbitrum:0xe47ba52f326806559c1deC7ddd997F6957d0317D',
+    'arbitrum:0x83e5Ecd192eAc043B0674A16EEDf96176726A159',
+    'arbitrum:0xA533f744B179F2431f5395978e391107DC76e103',
+    'arbitrum:0x4F604735c1cF31399C6E711D5962b2B3E0225AD3',
+    'arbitrum:0xC760F9782F8ceA5B06D862574464729537159966',
+    'arbitrum:0x66E535e8D2ebf13F49F3D49e5c50395a97C137b1',
+    'arbitrum:0x3269a3C00AB86c753856fD135d97b87FACB0d848',
+    'arbitrum:0xC3323b6e71925b25943fB7369EE6769837e9C676',
+    'arbitrum:0x0721b3C9f19cfeF1d622C918DcD431960f35E060',
+  ]
+  for (const token of trackedTokens) {
+    const value = balances[token]
+    expect(typeof value).toBe('string')
+    expect(value).toMatch(/^\d+$/)
+    expect(BigInt(value)).toBeGreaterThan(0n)
+  }
 })
 
 test("Indexer - getTransactions", async () => {