diff --git a/crates/common/src/pbs/error.rs b/crates/common/src/pbs/error.rs
index 83ea4b6b..763bfd62 100644
--- a/crates/common/src/pbs/error.rs
+++ b/crates/common/src/pbs/error.rs
@@ -20,6 +20,9 @@ pub enum PbsError {
     #[error("relay response error. Code: {code}, err: {error_msg}")]
     RelayResponse { error_msg: String, code: u16 },
 
+    #[error("Response size exceeds 10MB! Got: {payload_size}")]
+    PayloadTooLarge { payload_size: usize },
+
     #[error("failed validating relay response: {0}")]
     Validation(#[from] ValidationError),
 
diff --git a/crates/common/src/pbs/relay.rs b/crates/common/src/pbs/relay.rs
index 903277b0..6802890d 100644
--- a/crates/common/src/pbs/relay.rs
+++ b/crates/common/src/pbs/relay.rs
@@ -15,6 +15,9 @@ use super::{
     HEADER_VERSION_KEY, HEADER_VERSION_VALUE,
 };
 use crate::{config::RelayConfig, DEFAULT_REQUEST_TIMEOUT};
+
+pub const MAX_SIZE: usize = 10 * 1024 * 1024;
+
 /// A parsed entry of the relay url in the format: scheme://pubkey@host
 #[derive(Debug, Clone)]
 pub struct RelayEntry {
diff --git a/crates/pbs/Cargo.toml b/crates/pbs/Cargo.toml
index 34d659e3..7d6809b1 100644
--- a/crates/pbs/Cargo.toml
+++ b/crates/pbs/Cargo.toml
@@ -37,4 +37,4 @@ thiserror.workspace = true
 eyre.workspace = true
 url.workspace = true
 uuid.workspace = true
-lazy_static.workspace = true
+lazy_static.workspace = true
\ No newline at end of file
diff --git a/crates/pbs/src/mev_boost/get_header.rs b/crates/pbs/src/mev_boost/get_header.rs
index e98b3e49..ee5fa339 100644
--- a/crates/pbs/src/mev_boost/get_header.rs
+++ b/crates/pbs/src/mev_boost/get_header.rs
@@ -11,7 +11,7 @@ use cb_common::{
     pbs::{
         error::{PbsError, ValidationError},
         GetHeaderParams, GetHeaderResponse, RelayClient, SignedExecutionPayloadHeader,
-        EMPTY_TX_ROOT_HASH, HEADER_SLOT_UUID_KEY, HEADER_START_TIME_UNIX_MS,
+        EMPTY_TX_ROOT_HASH, HEADER_SLOT_UUID_KEY, HEADER_START_TIME_UNIX_MS, MAX_SIZE,
     },
     signature::verify_signed_message,
     types::Chain,
@@ -244,13 +244,16 @@ async fn send_one_get_header(
     RELAY_STATUS_CODE.with_label_values(&[code.as_str(), GET_HEADER_ENDPOINT_TAG, &relay.id]).inc();
 
     let response_bytes = res.bytes().await?;
+    if response_bytes.len() > MAX_SIZE {
+        return Err(PbsError::PayloadTooLarge { payload_size: response_bytes.len() });
+    }
+
     if !code.is_success() {
         return Err(PbsError::RelayResponse {
             error_msg: String::from_utf8_lossy(&response_bytes).into_owned(),
             code: code.as_u16(),
         });
     };
-
     if code == StatusCode::NO_CONTENT {
         debug!(
             ?code,
diff --git a/crates/pbs/src/mev_boost/register_validator.rs b/crates/pbs/src/mev_boost/register_validator.rs
index d44ca2d3..5fcfc991 100644
--- a/crates/pbs/src/mev_boost/register_validator.rs
+++ b/crates/pbs/src/mev_boost/register_validator.rs
@@ -3,7 +3,7 @@ use std::time::{Duration, Instant};
 use alloy::rpc::types::beacon::relay::ValidatorRegistration;
 use axum::http::{HeaderMap, HeaderValue};
 use cb_common::{
-    pbs::{error::PbsError, RelayClient, HEADER_START_TIME_UNIX_MS},
+    pbs::{error::PbsError, RelayClient, HEADER_START_TIME_UNIX_MS, MAX_SIZE},
     utils::{get_user_agent_with_version, utcnow_ms},
 };
 use eyre::bail;
@@ -92,6 +92,9 @@ async fn send_register_validator(
         .inc();
 
     let response_bytes = res.bytes().await?;
+    if response_bytes.len() > MAX_SIZE {
+        return Err(PbsError::PayloadTooLarge { payload_size: response_bytes.len() });
+    }
     if !code.is_success() {
         let err = PbsError::RelayResponse {
             error_msg: String::from_utf8_lossy(&response_bytes).into_owned(),
diff --git a/crates/pbs/src/mev_boost/status.rs b/crates/pbs/src/mev_boost/status.rs
index 13b29035..514ef860 100644
--- a/crates/pbs/src/mev_boost/status.rs
+++ b/crates/pbs/src/mev_boost/status.rs
@@ -2,7 +2,7 @@ use std::time::{Duration, Instant};
 
 use axum::http::HeaderMap;
 use cb_common::{
-    pbs::{error::PbsError, RelayClient},
+    pbs::{error::PbsError, RelayClient, MAX_SIZE},
     utils::get_user_agent_with_version,
 };
 use futures::future::select_ok;
@@ -75,6 +75,9 @@ async fn send_relay_check(relay: &RelayClient, headers: HeaderMap) -> Result<(),
     RELAY_STATUS_CODE.with_label_values(&[code.as_str(), STATUS_ENDPOINT_TAG, &relay.id]).inc();
 
     let response_bytes = res.bytes().await?;
+    if response_bytes.len() > MAX_SIZE {
+        return Err(PbsError::PayloadTooLarge { payload_size: response_bytes.len() });
+    }
     if !code.is_success() {
         let err = PbsError::RelayResponse {
             error_msg: String::from_utf8_lossy(&response_bytes).into_owned(),
diff --git a/crates/pbs/src/mev_boost/submit_block.rs b/crates/pbs/src/mev_boost/submit_block.rs
index 9ae83df0..e430ca32 100644
--- a/crates/pbs/src/mev_boost/submit_block.rs
+++ b/crates/pbs/src/mev_boost/submit_block.rs
@@ -5,7 +5,7 @@ use cb_common::{
     pbs::{
         error::{PbsError, ValidationError},
         RelayClient, SignedBlindedBeaconBlock, SubmitBlindedBlockResponse, HEADER_SLOT_UUID_KEY,
-        HEADER_START_TIME_UNIX_MS,
+        HEADER_START_TIME_UNIX_MS, MAX_SIZE,
     },
     utils::{get_user_agent_with_version, utcnow_ms},
 };
@@ -95,6 +95,10 @@ async fn send_submit_block(
         .inc();
 
     let response_bytes = res.bytes().await?;
+
+    if response_bytes.len() > MAX_SIZE {
+        return Err(PbsError::PayloadTooLarge { payload_size: response_bytes.len() });
+    }
     if !code.is_success() {
         let err = PbsError::RelayResponse {
             error_msg: String::from_utf8_lossy(&response_bytes).into_owned(),