diff --git a/packages/transaction-pay-controller/CHANGELOG.md b/packages/transaction-pay-controller/CHANGELOG.md
index ad2778123f..b6a3faf7dc 100644
--- a/packages/transaction-pay-controller/CHANGELOG.md
+++ b/packages/transaction-pay-controller/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Add Gas Station support for Across source transactions when native balance is insufficient ([#8588](https://github.com/MetaMask/core/pull/8588))
 
+### Fixed
+
+- Pass explicit `assetId`, `providers`, and `fiat` to `RampsController:getQuotes` and persist the selected ramps quote on `TransactionFiatPayment` ([#8628](https://github.com/MetaMask/core/pull/8628))
+
 ## [20.2.0]
 
 ### Changed
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/constants.ts b/packages/transaction-pay-controller/src/strategy/fiat/constants.ts
index 720be2ff02..5289ebcb82 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/constants.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/constants.ts
@@ -7,6 +7,8 @@ import {
   NATIVE_TOKEN_ADDRESS,
 } from '../../constants';
 
+export const DEFAULT_FIAT_CURRENCY = 'USD';
+
 export type TransactionPayFiatAsset = {
   address: Hex;
   caipAssetId: string;
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.test.ts b/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.test.ts
index e874cba533..0bc9d291fd 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.test.ts
@@ -9,6 +9,7 @@ import type { Hex } from '@metamask/utils';
 import { TransactionPayStrategy } from '../../constants';
 import type {
   PayStrategyGetQuotesRequest,
+  TransactionFiatPayment,
   TransactionPayQuote,
   TransactionPayRequiredToken,
 } from '../../types';
@@ -17,7 +18,7 @@ import { getRelayQuotes } from '../relay/relay-quotes';
 import type { RelayQuote } from '../relay/types';
 import type { TransactionPayFiatAsset } from './constants';
 import { getFiatQuotes } from './fiat-quotes';
-import { deriveFiatAssetForFiatPayment, pickBestFiatQuote } from './utils';
+import { deriveFiatAssetForFiatPayment } from './utils';
 
 jest.mock('../relay/relay-quotes');
 jest.mock('../../utils/token');
@@ -67,6 +68,8 @@ const FIAT_QUOTE_MOCK: RampsQuote = {
   },
 };
 
+const SELECTED_PROVIDER_ID = '/providers/transak-native-staging';
+
 const FIAT_QUOTES_RESPONSE_MOCK: RampsQuotesResponse = {
   customActions: [],
   error: [],
@@ -123,47 +126,69 @@ function getRequest({
   amountFiat = '10',
   fiatPaymentMethod = '/payments/debit-credit-card',
   rampsQuotes = FIAT_QUOTES_RESPONSE_MOCK,
+  selectedProviderId = SELECTED_PROVIDER_ID as string | null,
   tokens = [REQUIRED_TOKEN_MOCK],
   throwsOnRampsQuotes,
 }: {
   amountFiat?: string;
   fiatPaymentMethod?: string;
   rampsQuotes?: RampsQuotesResponse;
+  selectedProviderId?: string | null;
   tokens?: TransactionPayRequiredToken[];
   throwsOnRampsQuotes?: Error;
 } = {}): {
   callMock: jest.Mock;
   request: PayStrategyGetQuotesRequest;
 } {
-  const callMock = jest.fn((action: string) => {
-    if (action === 'TransactionPayController:getState') {
-      return {
-        transactionData: {
-          [TRANSACTION_ID]: {
-            fiatPayment: {
-              amountFiat,
+  const callMock = jest.fn(
+    (action: string, requestArg?: Record<string, unknown>) => {
+      if (action === 'TransactionPayController:getState') {
+        return {
+          transactionData: {
+            [TRANSACTION_ID]: {
+              fiatPayment: {
+                amountFiat,
+              },
+              isLoading: false,
+              tokens,
             },
-            isLoading: false,
-            tokens,
           },
-        },
-      };
-    }
+        };
+      }
 
-    if (action === 'RampsController:getQuotes') {
-      if (throwsOnRampsQuotes) {
-        throw throwsOnRampsQuotes;
+      if (action === 'RampsController:getState') {
+        return {
+          providers: {
+            selected: selectedProviderId ? { id: selectedProviderId } : null,
+          },
+        };
       }
 
-      return rampsQuotes;
-    }
+      if (action === 'RampsController:getQuotes') {
+        if (throwsOnRampsQuotes) {
+          throw throwsOnRampsQuotes;
+        }
 
-    throw new Error(`Unexpected action: ${action}`);
-  });
+        return rampsQuotes;
+      }
+
+      if (action === 'TransactionPayController:updateFiatPayment') {
+        const { callback } = requestArg as unknown as {
+          callback: (fiatPayment: TransactionFiatPayment) => void;
+        };
+        const fiatPayment: TransactionFiatPayment = {};
+        callback(fiatPayment);
+        return undefined;
+      }
+
+      throw new Error(`Unexpected action: ${action}`);
+    },
+  );
 
   return {
     callMock,
     request: {
+      accountSupports7702: false,
       fiatPaymentMethod,
       messenger: {
         call: callMock,
@@ -181,7 +206,6 @@ describe('getFiatQuotes', () => {
   const deriveFiatAssetForFiatPaymentMock = jest.mocked(
     deriveFiatAssetForFiatPayment,
   );
-  const pickBestFiatQuoteMock = jest.mocked(pickBestFiatQuote);
 
   beforeEach(() => {
     jest.resetAllMocks();
@@ -193,7 +217,6 @@ describe('getFiatQuotes', () => {
     });
     computeRawFromFiatAmountMock.mockReturnValue('5000000000000000000');
     getRelayQuotesMock.mockResolvedValue([getRelayQuoteMock()]);
-    pickBestFiatQuoteMock.mockReturnValue(FIAT_QUOTE_MOCK);
   });
 
   it('returns combined fiat quote and calls ramps with adjusted amount', async () => {
@@ -219,11 +242,22 @@ describe('getFiatQuotes', () => {
       'RampsController:getQuotes',
       expect.objectContaining({
         amount: 20,
+        assetId: FIAT_ASSET_MOCK.caipAssetId,
+        fiat: 'USD',
         paymentMethods: ['/payments/debit-credit-card'],
+        providers: [SELECTED_PROVIDER_ID],
         walletAddress: WALLET_ADDRESS,
       }),
     );
 
+    expect(callMock).toHaveBeenCalledWith(
+      'TransactionPayController:updateFiatPayment',
+      expect.objectContaining({
+        callback: expect.any(Function),
+        transactionId: TRANSACTION_ID,
+      }),
+    );
+
     expect(result).toHaveLength(1);
     expect(result[0].strategy).toBe(TransactionPayStrategy.Fiat);
     // provider = relay(1) + ramps(0.7) = 1.7
@@ -301,16 +335,15 @@ describe('getFiatQuotes', () => {
       throw new Error(`Unexpected action: ${action}`);
     });
 
-    const request: PayStrategyGetQuotesRequest = {
+    const result = await getFiatQuotes({
+      accountSupports7702: false,
       fiatPaymentMethod: '/payments/debit-credit-card',
       messenger: {
         call: callMock,
       } as unknown as PayStrategyGetQuotesRequest['messenger'],
       requests: [],
       transaction: TRANSACTION_MOCK,
-    };
-
-    const result = await getFiatQuotes(request);
+    });
 
     expect(result).toStrictEqual([]);
     expect(getRelayQuotesMock).not.toHaveBeenCalled();
@@ -425,9 +458,15 @@ describe('getFiatQuotes', () => {
     );
   });
 
-  it('returns empty array if preferred fiat quote is missing', async () => {
-    pickBestFiatQuoteMock.mockReturnValue(undefined);
-    const { request } = getRequest();
+  it('returns empty array if no quotes in success array', async () => {
+    const { request } = getRequest({
+      rampsQuotes: {
+        customActions: [],
+        error: [],
+        sorted: [],
+        success: [],
+      },
+    });
 
     const result = await getFiatQuotes(request);
 
@@ -435,7 +474,6 @@ describe('getFiatQuotes', () => {
   });
 
   it('handles ramps response without success property', async () => {
-    pickBestFiatQuoteMock.mockReturnValue(undefined);
     const { request } = getRequest({
       rampsQuotes: {
         customActions: [],
@@ -449,6 +487,72 @@ describe('getFiatQuotes', () => {
     expect(result).toStrictEqual([]);
   });
 
+  it('passes undefined providers when no provider is selected', async () => {
+    const { callMock, request } = getRequest({
+      selectedProviderId: null,
+    });
+
+    await getFiatQuotes(request);
+
+    expect(callMock).toHaveBeenCalledWith(
+      'RampsController:getQuotes',
+      expect.objectContaining({
+        providers: undefined,
+      }),
+    );
+  });
+
+  it('stores rampsQuote on fiat payment state via updateFiatPayment', async () => {
+    const fiatPaymentState: TransactionFiatPayment = {};
+    const callMock = jest.fn(
+      (action: string, requestArg?: Record<string, unknown>) => {
+        if (action === 'TransactionPayController:getState') {
+          return {
+            transactionData: {
+              [TRANSACTION_ID]: {
+                fiatPayment: { amountFiat: '10' },
+                isLoading: false,
+                tokens: [REQUIRED_TOKEN_MOCK],
+              },
+            },
+          };
+        }
+
+        if (action === 'RampsController:getState') {
+          return {
+            providers: { selected: { id: SELECTED_PROVIDER_ID } },
+          };
+        }
+
+        if (action === 'RampsController:getQuotes') {
+          return FIAT_QUOTES_RESPONSE_MOCK;
+        }
+
+        if (action === 'TransactionPayController:updateFiatPayment') {
+          const { callback } = requestArg as unknown as {
+            callback: (fp: TransactionFiatPayment) => void;
+          };
+          callback(fiatPaymentState);
+          return undefined;
+        }
+
+        throw new Error(`Unexpected action: ${action}`);
+      },
+    );
+
+    await getFiatQuotes({
+      accountSupports7702: false,
+      fiatPaymentMethod: '/payments/debit-credit-card',
+      messenger: {
+        call: callMock,
+      } as unknown as PayStrategyGetQuotesRequest['messenger'],
+      requests: [],
+      transaction: TRANSACTION_MOCK,
+    });
+
+    expect(fiatPaymentState.rampsQuote).toStrictEqual(FIAT_QUOTE_MOCK);
+  });
+
   it('returns empty array if ramps quotes fetch throws', async () => {
     const { request } = getRequest({
       throwsOnRampsQuotes: new Error('ramps failed'),
@@ -474,15 +578,22 @@ describe('getFiatQuotes', () => {
   });
 
   it('sets providerFiat fee to zero when ramps provider/network fees are missing', async () => {
-    pickBestFiatQuoteMock.mockReturnValue({
+    const quoteWithoutFees: RampsQuote = {
       provider: '/providers/transak-native-staging',
       quote: {
         amountIn: 20,
         amountOut: 5,
         paymentMethod: '/payments/debit-credit-card',
       },
-    } as RampsQuote);
-    const { request } = getRequest();
+    };
+    const { request } = getRequest({
+      rampsQuotes: {
+        customActions: [],
+        error: [],
+        sorted: [],
+        success: [quoteWithoutFees],
+      },
+    });
 
     const result = await getFiatQuotes(request);
 
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.ts b/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.ts
index 959631c601..a4184af3d8 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/fiat-quotes.ts
@@ -14,8 +14,10 @@ import type {
 import { computeRawFromFiatAmount, getTokenFiatRate } from '../../utils/token';
 import { getRelayQuotes } from '../relay/relay-quotes';
 import type { RelayQuote } from '../relay/types';
+import { DEFAULT_FIAT_CURRENCY } from './constants';
+import type { TransactionPayFiatAsset } from './constants';
 import type { FiatQuote } from './types';
-import { deriveFiatAssetForFiatPayment, pickBestFiatQuote } from './utils';
+import { deriveFiatAssetForFiatPayment } from './utils';
 
 const log = createModuleLogger(projectLogger, 'fiat-strategy');
 
@@ -115,23 +117,21 @@ export async function getFiatQuotes(
       transactionId,
     });
 
-    const quotes = await messenger.call('RampsController:getQuotes', {
-      amount: adjustedAmount,
-      paymentMethods: [fiatPaymentMethod],
+    const fiatQuote = await getRampsQuote({
+      adjustedAmount,
+      fiatAsset,
+      fiatPaymentMethod,
+      messenger,
       walletAddress,
     });
 
-    log('Fetched ramps quotes', {
-      rampsQuotesCount: quotes.success?.length ?? 0,
+    messenger.call('TransactionPayController:updateFiatPayment', {
+      callback: (fiatPayment) => {
+        fiatPayment.rampsQuote = fiatQuote;
+      },
       transactionId,
     });
 
-    const fiatQuote = pickBestFiatQuote(quotes);
-
-    if (!fiatQuote) {
-      throw new Error('No matching ramps quote found for selected provider');
-    }
-
     return [
       combineQuotes({
         adjustedAmountFiat: adjustedAmountFiat.toString(10),
@@ -153,6 +153,45 @@ function getRequiredTokens(
   return tokens?.filter((token) => !token.skipIfBalance) ?? [];
 }
 
+async function getRampsQuote({
+  adjustedAmount,
+  fiatAsset,
+  fiatPaymentMethod,
+  messenger,
+  walletAddress,
+}: {
+  adjustedAmount: number;
+  fiatAsset: TransactionPayFiatAsset;
+  fiatPaymentMethod: string;
+  messenger: PayStrategyGetQuotesRequest['messenger'];
+  walletAddress: string;
+}): Promise<RampsQuote> {
+  const rampsState = messenger.call('RampsController:getState');
+  const selectedProviderId = rampsState.providers.selected?.id;
+
+  const quotes = await messenger.call('RampsController:getQuotes', {
+    amount: adjustedAmount,
+    assetId: fiatAsset.caipAssetId,
+    fiat: DEFAULT_FIAT_CURRENCY,
+    paymentMethods: [fiatPaymentMethod],
+    providers: selectedProviderId ? [selectedProviderId] : undefined,
+    walletAddress,
+  });
+
+  log('Fetched ramps quotes', {
+    quotesCount: quotes.success?.length ?? 0,
+    selectedProviderId,
+  });
+
+  const quote = quotes.success?.[0];
+
+  if (!quote) {
+    throw new Error('No matching ramps quote found for selected provider');
+  }
+
+  return quote;
+}
+
 function buildRelayRequestFromAmountFiat({
   amountFiat,
   fiatAsset,
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/types.ts b/packages/transaction-pay-controller/src/strategy/fiat/types.ts
index d009c27f69..8e5b53ef6b 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/types.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/types.ts
@@ -1,4 +1,4 @@
-import type { Quote, QuotesResponse } from '@metamask/ramps-controller';
+import type { Quote } from '@metamask/ramps-controller';
 
 import type { RelayQuote } from '../relay/types';
 
@@ -6,5 +6,3 @@ export type FiatQuote = {
   rampsQuote: Quote;
   relayQuote: RelayQuote;
 };
-
-export type FiatQuotesResponse = QuotesResponse;
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/utils.test.ts b/packages/transaction-pay-controller/src/strategy/fiat/utils.test.ts
index b1f997afda..1175bccd56 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/utils.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/utils.test.ts
@@ -2,8 +2,7 @@ import type { TransactionMeta } from '@metamask/transaction-controller';
 import { TransactionType } from '@metamask/transaction-controller';
 
 import { FIAT_ASSET_ID_BY_TX_TYPE } from './constants';
-import type { FiatQuotesResponse } from './types';
-import { deriveFiatAssetForFiatPayment, pickBestFiatQuote } from './utils';
+import { deriveFiatAssetForFiatPayment } from './utils';
 
 describe('Fiat Utils', () => {
   describe('deriveFiatAssetForFiatPayment', () => {
@@ -42,46 +41,4 @@ describe('Fiat Utils', () => {
       expect(result).toBeUndefined();
     });
   });
-
-  describe('pickBestFiatQuote', () => {
-    it('returns transak-native-staging quote when present', () => {
-      const quotes = {
-        customActions: [],
-        error: [],
-        sorted: [],
-        success: [
-          {
-            provider: '/providers/moonpay',
-            quote: { amountIn: 10, amountOut: 20, paymentMethod: 'card' },
-          },
-          {
-            provider: '/providers/transak-native-staging',
-            quote: { amountIn: 11, amountOut: 22, paymentMethod: 'card' },
-          },
-        ],
-      } as FiatQuotesResponse;
-
-      const result = pickBestFiatQuote(quotes);
-
-      expect(result).toStrictEqual(quotes.success[1]);
-    });
-
-    it('returns undefined when transak-native-staging quote is missing', () => {
-      const quotes = {
-        customActions: [],
-        error: [],
-        sorted: [],
-        success: [
-          {
-            provider: '/providers/moonpay',
-            quote: { amountIn: 10, amountOut: 20, paymentMethod: 'card' },
-          },
-        ],
-      } as FiatQuotesResponse;
-
-      const result = pickBestFiatQuote(quotes);
-
-      expect(result).toBeUndefined();
-    });
-  });
 });
diff --git a/packages/transaction-pay-controller/src/strategy/fiat/utils.ts b/packages/transaction-pay-controller/src/strategy/fiat/utils.ts
index 73f2017e15..6894127b13 100644
--- a/packages/transaction-pay-controller/src/strategy/fiat/utils.ts
+++ b/packages/transaction-pay-controller/src/strategy/fiat/utils.ts
@@ -1,7 +1,3 @@
-import type {
-  Quote as RampsQuote,
-  QuotesResponse as RampsQuotesResponse,
-} from '@metamask/ramps-controller';
 import {
   TransactionMeta,
   TransactionType,
@@ -23,12 +19,3 @@ export function deriveFiatAssetForFiatPayment(
 
   return FIAT_ASSET_ID_BY_TX_TYPE[transactionType as TransactionType];
 }
-
-export function pickBestFiatQuote(
-  quotes: RampsQuotesResponse,
-): RampsQuote | undefined {
-  return quotes.success?.find(
-    // TODO: Implement provider selection logic; force Transak staging for now.
-    (quote) => quote.provider === '/providers/transak-native-staging',
-  );
-}
diff --git a/packages/transaction-pay-controller/src/types.ts b/packages/transaction-pay-controller/src/types.ts
index 41cdc70b8c..c8000178e2 100644
--- a/packages/transaction-pay-controller/src/types.ts
+++ b/packages/transaction-pay-controller/src/types.ts
@@ -20,7 +20,11 @@ import type {
 import type { Messenger } from '@metamask/messenger';
 import type { NetworkControllerFindNetworkClientIdByChainIdAction } from '@metamask/network-controller';
 import type { NetworkControllerGetNetworkClientByIdAction } from '@metamask/network-controller';
-import type { RampsControllerGetQuotesAction } from '@metamask/ramps-controller';
+import type { Quote as RampsQuote } from '@metamask/ramps-controller';
+import type {
+  RampsControllerGetQuotesAction,
+  RampsControllerGetStateAction,
+} from '@metamask/ramps-controller';
 import type { RemoteFeatureFlagControllerGetStateAction } from '@metamask/remote-feature-flag-controller';
 import type {
   AuthorizationList,
@@ -56,6 +60,7 @@ export type AllowedActions =
   | NetworkControllerFindNetworkClientIdByChainIdAction
   | NetworkControllerGetNetworkClientByIdAction
   | RampsControllerGetQuotesAction
+  | RampsControllerGetStateAction
   | RemoteFeatureFlagControllerGetStateAction
   | TokenBalancesControllerGetStateAction
   | TokenRatesControllerGetStateAction
@@ -239,6 +244,9 @@ export type TransactionFiatPayment = {
   /** Entered fiat amount for the selected payment method. */
   amountFiat?: string;
 
+  /** The ramps quote received from the ramps provider. */
+  rampsQuote?: RampsQuote;
+
   /** Selected fiat payment method ID. */
   selectedPaymentMethodId?: string;
 };