diff --git a/packages/api/src/keymanager/index.ts b/packages/api/src/keymanager/index.ts
index 1ffcaef897e..44252acce49 100644
--- a/packages/api/src/keymanager/index.ts
+++ b/packages/api/src/keymanager/index.ts
@@ -18,6 +18,7 @@ export type {
   GraffitiData,
   GasLimitData,
   BuilderBoostFactorData,
+  ProposerConfigResponse,
 } from "./routes.js";
 
 export type {ApiClient};
diff --git a/packages/api/src/keymanager/routes.ts b/packages/api/src/keymanager/routes.ts
index 0db096d14e8..c31ae5a0445 100644
--- a/packages/api/src/keymanager/routes.ts
+++ b/packages/api/src/keymanager/routes.ts
@@ -109,6 +109,17 @@ export type SignerDefinition = {
 
 export type RemoteSignerDefinition = Pick<SignerDefinition, "pubkey" | "url">;
 
+export type ProposerConfigResponse = {
+  graffiti?: string;
+  strictFeeRecipientCheck?: boolean;
+  feeRecipient?: string;
+  builder?: {
+    gasLimit?: number;
+    selection?: string;
+    boostFactor?: string;
+  };
+};
+
 /**
  * JSON serialized representation of a single keystore in EIP-2335: BLS12-381 Keystore format.
  * ```
@@ -356,6 +367,15 @@ export type Endpoints = {
     EmptyMeta
   >;
 
+  getProposerConfig: Endpoint<
+    // ⏎
+    "GET",
+    {pubkey: PubkeyHex},
+    {params: {pubkey: string}},
+    ProposerConfigResponse,
+    EmptyMeta
+  >;
+
   /**
    * Create a signed voluntary exit message for an active validator, identified by a public key known to the validator
    * client. This endpoint returns a `SignedVoluntaryExit` object, which can be used to initiate voluntary exit via the
@@ -635,6 +655,19 @@ export function getDefinitions(_config: ChainForkConfig): RouteDefinitions<Endpo
       resp: EmptyResponseCodec,
     },
 
+    getProposerConfig: {
+      url: "/eth/v0/validator/{pubkey}/proposer_config",
+      method: "GET",
+      req: {
+        writeReq: ({pubkey}) => ({params: {pubkey}}),
+        parseReq: ({params: {pubkey}}) => ({pubkey}),
+        schema: {
+          params: {pubkey: Schema.StringRequired},
+        },
+      },
+      resp: JsonOnlyResponseCodec,
+    },
+
     signVoluntaryExit: {
       url: "/eth/v1/validator/{pubkey}/voluntary_exit",
       method: "POST",
diff --git a/packages/api/test/unit/keymanager/testData.ts b/packages/api/test/unit/keymanager/testData.ts
index bd37798c468..6b17611d1e0 100644
--- a/packages/api/test/unit/keymanager/testData.ts
+++ b/packages/api/test/unit/keymanager/testData.ts
@@ -112,4 +112,19 @@ export const testData: GenericServerTestCases<Endpoints> = {
     args: {pubkey: pubkeyRand},
     res: undefined,
   },
+  getProposerConfig: {
+    args: {pubkey: pubkeyRand},
+    res: {
+      data: {
+        graffiti: graffitiRandUtf8,
+        strictFeeRecipientCheck: false,
+        feeRecipient: ethaddressRand,
+        builder: {
+          gasLimit: gasLimitRand,
+          selection: "maxprofit",
+          boostFactor: builderBoostFactorRand.toString(),
+        },
+      },
+    },
+  },
 };
diff --git a/packages/cli/src/cmds/validator/keymanager/impl.ts b/packages/cli/src/cmds/validator/keymanager/impl.ts
index b4233f3162c..545f2f74f06 100644
--- a/packages/cli/src/cmds/validator/keymanager/impl.ts
+++ b/packages/cli/src/cmds/validator/keymanager/impl.ts
@@ -15,6 +15,7 @@ import {
   GraffitiData,
   GasLimitData,
   BuilderBoostFactorData,
+  ProposerConfigResponse,
 } from "@lodestar/api/keymanager";
 import {KeymanagerApiMethods as Api} from "@lodestar/api/keymanager/server";
 import {Interchange, SignerType, Validator} from "@lodestar/validator";
@@ -364,6 +365,23 @@ export class KeymanagerApi implements Api {
     return {status: 204};
   }
 
+  async getProposerConfig({pubkey}: {pubkey: PubkeyHex}): ReturnType<Api["getProposerConfig"]> {
+    const config = this.validator.validatorStore.getProposerConfig(pubkey);
+
+    const data: ProposerConfigResponse = {
+      ...config,
+      builder: config?.builder
+        ? {
+            ...config.builder,
+            // Default JSON serialization can't handle BigInt
+            boostFactor: config.builder.boostFactor ? config.builder.boostFactor.toString() : undefined,
+          }
+        : undefined,
+    };
+
+    return {data};
+  }
+
   async signVoluntaryExit({pubkey, epoch}: {pubkey: PubkeyHex; epoch?: Epoch}): ReturnType<Api["signVoluntaryExit"]> {
     if (!isValidatePubkeyHex(pubkey)) {
       throw new ApiError(400, `Invalid pubkey ${pubkey}`);
diff --git a/packages/cli/src/util/proposerConfig.ts b/packages/cli/src/util/proposerConfig.ts
index 2c12ce8f852..4cfa6fa7107 100644
--- a/packages/cli/src/util/proposerConfig.ts
+++ b/packages/cli/src/util/proposerConfig.ts
@@ -88,11 +88,14 @@ function parseProposerConfigSection(
       overrideConfig?.strictFeeRecipientCheck ??
       (strict_fee_recipient_check ? stringtoBool(strict_fee_recipient_check) : undefined),
     feeRecipient: overrideConfig?.feeRecipient ?? (fee_recipient ? parseFeeRecipient(fee_recipient) : undefined),
-    builder: {
-      gasLimit: overrideConfig?.builder?.gasLimit ?? (gas_limit !== undefined ? Number(gas_limit) : undefined),
-      selection: overrideConfig?.builder?.selection ?? parseBuilderSelection(builderSelection),
-      boostFactor: overrideConfig?.builder?.boostFactor ?? parseBuilderBoostFactor(boost_factor),
-    },
+    builder:
+      overrideConfig?.builder || builder
+        ? {
+            gasLimit: overrideConfig?.builder?.gasLimit ?? (gas_limit !== undefined ? Number(gas_limit) : undefined),
+            selection: overrideConfig?.builder?.selection ?? parseBuilderSelection(builderSelection),
+            boostFactor: overrideConfig?.builder?.boostFactor ?? parseBuilderBoostFactor(boost_factor),
+          }
+        : undefined,
   };
 }
 
diff --git a/packages/cli/test/unit/validator/parseProposerConfig.test.ts b/packages/cli/test/unit/validator/parseProposerConfig.test.ts
index 83c8c63ef87..40fa57f7feb 100644
--- a/packages/cli/test/unit/validator/parseProposerConfig.test.ts
+++ b/packages/cli/test/unit/validator/parseProposerConfig.test.ts
@@ -26,8 +26,7 @@ const testValue = {
       builder: {
         gasLimit: 35000000,
         selection: routes.validator.BuilderSelection.BuilderAlways,
-        // biome-ignore lint/correctness/noPrecisionLoss: <explanation>
-        boostFactor: BigInt(18446744073709551616),
+        boostFactor: 18446744073709551616n,
       },
     },
   },
diff --git a/packages/validator/src/services/validatorStore.ts b/packages/validator/src/services/validatorStore.ts
index dfd856b18d1..f959b4e74ff 100644
--- a/packages/validator/src/services/validatorStore.ts
+++ b/packages/validator/src/services/validatorStore.ts
@@ -377,7 +377,9 @@ export class ValidatorStore {
       graffiti !== undefined ||
       strictFeeRecipientCheck !== undefined ||
       feeRecipient !== undefined ||
-      builder?.gasLimit !== undefined
+      builder?.gasLimit !== undefined ||
+      builder?.selection !== undefined ||
+      builder?.boostFactor !== undefined
     ) {
       proposerConfig = {graffiti, strictFeeRecipientCheck, feeRecipient, builder};
     }