diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 9da64888c2..5a9b6b8c87 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -3150,7 +3150,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             };
 
             // Import the blocks into the chain.
-            for signature_verified_block in signature_verified_blocks {
+            for (signature_verified_block, _envelope) in signature_verified_blocks {
                 let block_slot = signature_verified_block.slot();
                 match self
                     .process_block(
diff --git a/beacon_node/beacon_chain/src/block_verification.rs b/beacon_node/beacon_chain/src/block_verification.rs
index 9a43147233..7a81a4465e 100644
--- a/beacon_node/beacon_chain/src/block_verification.rs
+++ b/beacon_node/beacon_chain/src/block_verification.rs
@@ -60,6 +60,7 @@ use crate::execution_payload::{
 };
 use crate::kzg_utils::blobs_to_data_column_sidecars;
 use crate::observed_block_producers::SeenBlock;
+use crate::payload_envelope_verification::{AvailableEnvelope, EnvelopeError};
 use crate::validator_monitor::HISTORIC_EPOCHS as VALIDATOR_MONITOR_HISTORIC_EPOCHS;
 use crate::validator_pubkey_cache::ValidatorPubkeyCache;
 use crate::{
@@ -320,6 +321,20 @@ pub enum BlockError {
         bid_parent_root: Hash256,
         block_parent_root: Hash256,
     },
+    /// The child block is known but its parent execution payload envelope has not been received yet.
+    ///
+    /// ## Peer scoring
+    ///
+    /// It's unclear if this block is valid, but it cannot be fully verified without the parent's
+    /// execution payload envelope.
+    ParentEnvelopeUnknown { parent_root: Hash256 },
+    /// An error occurred while processing the execution payload envelope during range sync.
+    EnvelopeError(Box<EnvelopeError>),
+
+    PayloadEnvelopeError {
+        e: Box<EnvelopeError>,
+        penalize_peer: bool,
+    },
 }
 
 /// Which specific signature(s) are invalid in a SignedBeaconBlock
@@ -486,6 +501,36 @@ impl From<ArithError> for BlockError {
     }
 }
 
+impl From<EnvelopeError> for BlockError {
+    fn from(e: EnvelopeError) -> Self {
+        let penalize_peer = match &e {
+            // REJECT per spec: peer sent invalid envelope data
+            EnvelopeError::BadSignature
+            | EnvelopeError::BuilderIndexMismatch { .. }
+            | EnvelopeError::BlockHashMismatch { .. }
+            | EnvelopeError::SlotMismatch { .. }
+            | EnvelopeError::IncorrectBlockProposer { .. } => true,
+            // IGNORE per spec: not the peer's fault
+            EnvelopeError::BlockRootUnknown { .. }
+            | EnvelopeError::PriorToFinalization { .. }
+            | EnvelopeError::UnknownValidator { .. } => false,
+            // Internal errors: not the peer's fault
+            EnvelopeError::BeaconChainError(_)
+            | EnvelopeError::BeaconStateError(_)
+            | EnvelopeError::BlockProcessingError(_)
+            | EnvelopeError::EnvelopeProcessingError(_)
+            | EnvelopeError::ExecutionPayloadError(_)
+            | EnvelopeError::BlockError(_)
+            | EnvelopeError::InternalError(_)
+            | EnvelopeError::OptimisticSyncNotSupported { .. } => false,
+        };
+        BlockError::PayloadEnvelopeError {
+            e: Box::new(e),
+            penalize_peer,
+        }
+    }
+}
+
 /// Stores information about verifying a payload against an execution engine.
 #[derive(Debug, PartialEq, Clone, Encode, Decode)]
 pub struct PayloadVerificationOutcome {
@@ -583,10 +628,17 @@ pub(crate) fn process_block_slash_info<T: BeaconChainTypes, TErr: BlockBlobError
 /// The given `chain_segment` must contain only blocks from the same epoch, otherwise an error
 /// will be returned.
 #[instrument(skip_all)]
+#[allow(clippy::type_complexity)]
 pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
     mut chain_segment: Vec<(Hash256, RangeSyncBlock<T::EthSpec>)>,
     chain: &BeaconChain<T>,
-) -> Result<Vec<SignatureVerifiedBlock<T>>, BlockError> {
+) -> Result<
+    Vec<(
+        SignatureVerifiedBlock<T>,
+        Option<Box<AvailableEnvelope<T::EthSpec>>>,
+    )>,
+    BlockError,
+> {
     if chain_segment.is_empty() {
         return Ok(vec![]);
     }
@@ -615,14 +667,29 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
         let consensus_context =
             ConsensusContext::new(block.slot()).set_current_block_root(block_root);
 
-        let available_block = block.into_available_block();
+        let (available_block, envelope) = match block {
+            RangeSyncBlock::Base(ab) => (ab, None),
+            RangeSyncBlock::Gloas { block, envelope } => {
+                let ab = AvailableBlock::new(
+                    block,
+                    AvailableBlockData::NoData,
+                    &chain.data_availability_checker,
+                    chain.spec.clone(),
+                )
+                .map_err(BlockError::AvailabilityCheck)?;
+                (ab, envelope)
+            }
+        };
         available_blocks.push(available_block.clone());
-        signature_verified_blocks.push(SignatureVerifiedBlock {
-            block: MaybeAvailableBlock::Available(available_block),
-            block_root,
-            parent: None,
-            consensus_context,
-        });
+        signature_verified_blocks.push((
+            SignatureVerifiedBlock {
+                block: MaybeAvailableBlock::Available(available_block),
+                block_root,
+                parent: None,
+                consensus_context,
+            },
+            envelope,
+        ));
     }
 
     chain
@@ -632,7 +699,7 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
     // verify signatures
     let pubkey_cache = get_validator_pubkey_cache(chain)?;
     let mut signature_verifier = get_signature_verifier(&state, &pubkey_cache, &chain.spec);
-    for svb in &mut signature_verified_blocks {
+    for (svb, _) in &mut signature_verified_blocks {
         signature_verifier
             .include_all_signatures(svb.block.as_block(), &mut svb.consensus_context)?;
     }
@@ -643,7 +710,7 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
 
     drop(pubkey_cache);
 
-    if let Some(signature_verified_block) = signature_verified_blocks.first_mut() {
+    if let Some((signature_verified_block, _)) = signature_verified_blocks.first_mut() {
         signature_verified_block.parent = Some(parent);
     }
 
@@ -1191,7 +1258,7 @@ impl<T: BeaconChainTypes> SignatureVerifiedBlock<T> {
         let result = info_span!("signature_verify").in_scope(|| signature_verifier.verify());
         match result {
             Ok(_) => {
-                // gloas blocks are always available.
+                // Gloas blocks are always available — data arrives via the envelope.
                 let maybe_available = if chain
                     .spec
                     .fork_name_at_slot::<T::EthSpec>(block.slot())
@@ -1946,6 +2013,21 @@ fn load_parent<T: BeaconChainTypes, B: AsBlock<T::EthSpec>>(
                 BlockError::from(BeaconChainError::MissingBeaconBlock(block.parent_root()))
             })?;
 
+        // For post-Gloas parent blocks, the execution payload arrives via the envelope.
+        // If the parent's execution payload envelope hasn't arrived yet,
+        // return an unknown parent error so the block gets sent to the
+        // reprocess queue.
+        if chain
+            .spec
+            .fork_name_at_slot::<T::EthSpec>(parent_block.slot())
+            .gloas_enabled()
+        {
+            let _envelope = chain
+                .store
+                .get_payload_envelope(&root)?
+                .ok_or(BlockError::ParentEnvelopeUnknown { parent_root: root })?;
+        }
+
         // Load the parent block's state from the database, returning an error if it is not found.
         // It is an error because if we know the parent block we should also know the parent state.
         // Retrieve any state that is advanced through to at most `block.slot()`: this is
diff --git a/beacon_node/beacon_chain/src/block_verification_types.rs b/beacon_node/beacon_chain/src/block_verification_types.rs
index be73ef15d7..05a757e73d 100644
--- a/beacon_node/beacon_chain/src/block_verification_types.rs
+++ b/beacon_node/beacon_chain/src/block_verification_types.rs
@@ -2,10 +2,11 @@ use crate::data_availability_checker::{AvailabilityCheckError, DataAvailabilityC
 pub use crate::data_availability_checker::{
     AvailableBlock, AvailableBlockData, MaybeAvailableBlock,
 };
+use crate::payload_envelope_verification::AvailableEnvelope;
 use crate::{BeaconChainTypes, PayloadVerificationOutcome};
-use educe::Educe;
 use state_processing::ConsensusContext;
 use std::fmt::{Debug, Formatter};
+use std::hash::{Hash, Hasher};
 use std::sync::Arc;
 use types::data::BlobIdentifier;
 use types::{
@@ -45,38 +46,60 @@ impl<E: EthSpec> LookupBlock<E> {
 /// This includes any and all blobs/columns required, including zero if
 /// none are required. This can happen if the block is pre-deneb or if
 /// it's simply past the DA boundary.
-#[derive(Clone, Educe)]
-#[educe(Hash(bound(E: EthSpec)))]
-pub struct RangeSyncBlock<E: EthSpec> {
-    block: AvailableBlock<E>,
+pub enum RangeSyncBlock<E: EthSpec> {
+    Base(AvailableBlock<E>),
+    Gloas {
+        block: Arc<SignedBeaconBlock<E>>,
+        envelope: Option<Box<AvailableEnvelope<E>>>,
+    },
+}
+
+impl<E: EthSpec> Hash for RangeSyncBlock<E> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.block_root().hash(state);
+    }
 }
 
 impl<E: EthSpec> Debug for RangeSyncBlock<E> {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "RpcBlock({:?})", self.block_root())
+        write!(f, "RangeSyncBlock({:?})", self.block_root())
     }
 }
 
 impl<E: EthSpec> RangeSyncBlock<E> {
     pub fn block_root(&self) -> Hash256 {
-        self.block.block_root()
+        match self {
+            RangeSyncBlock::Base(block) => block.block_root(),
+            RangeSyncBlock::Gloas { block, .. } => block.canonical_root(),
+        }
     }
 
     pub fn as_block(&self) -> &SignedBeaconBlock<E> {
-        self.block.block()
+        match self {
+            RangeSyncBlock::Base(block) => block.block(),
+            RangeSyncBlock::Gloas { block, .. } => block,
+        }
     }
 
     pub fn block_cloned(&self) -> Arc<SignedBeaconBlock<E>> {
-        self.block.block_cloned()
+        match self {
+            RangeSyncBlock::Base(block) => block.block_cloned(),
+            RangeSyncBlock::Gloas { block, .. } => block.clone(),
+        }
     }
 
     pub fn block_data(&self) -> &AvailableBlockData<E> {
-        self.block.data()
+        match self {
+            RangeSyncBlock::Base(block) => block.data(),
+            RangeSyncBlock::Gloas { .. } => {
+                unreachable!("block_data called on Gloas variant — use envelope data instead")
+            }
+        }
     }
 }
 
 impl<E: EthSpec> RangeSyncBlock<E> {
-    /// Constructs an `RangeSyncBlock` from a block and availability data.
+    /// Constructs a `RangeSyncBlock` from a block and availability data.
     ///
     /// # Errors
     ///
@@ -94,32 +117,53 @@ impl<E: EthSpec> RangeSyncBlock<E> {
         T: BeaconChainTypes<EthSpec = E>,
     {
         let available_block = AvailableBlock::new(block, block_data, da_checker, spec)?;
-        Ok(Self {
-            block: available_block,
-        })
+        Ok(Self::Base(available_block))
+    }
+
+    pub fn new_gloas(
+        block: Arc<SignedBeaconBlock<E>>,
+        envelope: Option<Box<AvailableEnvelope<E>>>,
+    ) -> Self {
+        Self::Gloas { block, envelope }
     }
 
     #[allow(clippy::type_complexity)]
     pub fn deconstruct(self) -> (Hash256, Arc<SignedBeaconBlock<E>>, AvailableBlockData<E>) {
-        self.block.deconstruct()
+        match self {
+            RangeSyncBlock::Base(block) => block.deconstruct(),
+            RangeSyncBlock::Gloas { .. } => {
+                unreachable!("deconstruct called on Gloas variant")
+            }
+        }
     }
 
     pub fn n_blobs(&self) -> usize {
-        match self.block_data() {
-            AvailableBlockData::NoData | AvailableBlockData::DataColumns(_) => 0,
-            AvailableBlockData::Blobs(blobs) => blobs.len(),
+        match self {
+            RangeSyncBlock::Base(block) => match block.data() {
+                AvailableBlockData::NoData | AvailableBlockData::DataColumns(_) => 0,
+                AvailableBlockData::Blobs(blobs) => blobs.len(),
+            },
+            RangeSyncBlock::Gloas { .. } => 0,
         }
     }
 
     pub fn n_data_columns(&self) -> usize {
-        match self.block_data() {
-            AvailableBlockData::NoData | AvailableBlockData::Blobs(_) => 0,
-            AvailableBlockData::DataColumns(columns) => columns.len(),
+        match self {
+            RangeSyncBlock::Base(block) => match block.data() {
+                AvailableBlockData::NoData | AvailableBlockData::Blobs(_) => 0,
+                AvailableBlockData::DataColumns(columns) => columns.len(),
+            },
+            RangeSyncBlock::Gloas { .. } => 0,
         }
     }
 
     pub fn into_available_block(self) -> AvailableBlock<E> {
-        self.block
+        match self {
+            RangeSyncBlock::Base(block) => block,
+            RangeSyncBlock::Gloas { .. } => {
+                unreachable!("into_available_block called on Gloas variant")
+            }
+        }
     }
 }
 
@@ -387,31 +431,31 @@ impl<E: EthSpec> AsBlock<E> for AvailableBlock<E> {
 
 impl<E: EthSpec> AsBlock<E> for RangeSyncBlock<E> {
     fn slot(&self) -> Slot {
-        self.as_block().slot()
+        RangeSyncBlock::as_block(self).slot()
     }
     fn epoch(&self) -> Epoch {
-        self.as_block().epoch()
+        RangeSyncBlock::as_block(self).epoch()
     }
     fn parent_root(&self) -> Hash256 {
-        self.as_block().parent_root()
+        RangeSyncBlock::as_block(self).parent_root()
     }
     fn state_root(&self) -> Hash256 {
-        self.as_block().state_root()
+        RangeSyncBlock::as_block(self).state_root()
     }
     fn signed_block_header(&self) -> SignedBeaconBlockHeader {
-        self.as_block().signed_block_header()
+        RangeSyncBlock::as_block(self).signed_block_header()
     }
     fn message(&self) -> BeaconBlockRef<'_, E> {
-        self.as_block().message()
+        RangeSyncBlock::as_block(self).message()
     }
     fn as_block(&self) -> &SignedBeaconBlock<E> {
-        self.block.as_block()
+        RangeSyncBlock::as_block(self)
     }
     fn block_cloned(&self) -> Arc<SignedBeaconBlock<E>> {
-        self.block.block_cloned()
+        RangeSyncBlock::block_cloned(self)
     }
     fn canonical_root(&self) -> Hash256 {
-        self.block.block_root()
+        self.block_root()
     }
 }
 
diff --git a/beacon_node/beacon_chain/src/data_availability_checker.rs b/beacon_node/beacon_chain/src/data_availability_checker.rs
index 9d8b76aaed..e296f1b78d 100644
--- a/beacon_node/beacon_chain/src/data_availability_checker.rs
+++ b/beacon_node/beacon_chain/src/data_availability_checker.rs
@@ -21,7 +21,7 @@ use tracing::{debug, error, instrument};
 use types::data::{BlobIdentifier, FixedBlobSidecarList, PartialDataColumn};
 use types::{
     BlobSidecar, BlobSidecarList, BlockImportSource, ChainSpec, DataColumnSidecar,
-    DataColumnSidecarList, Epoch, EthSpec, Hash256, PartialDataColumnSidecarError,
+    DataColumnSidecarList, Epoch, EthSpec, ForkName, Hash256, PartialDataColumnSidecarError,
     PartialDataColumnSidecarRef, SignedBeaconBlock, Slot, new_non_zero_usize,
 };
 
@@ -540,6 +540,11 @@ impl<T: BeaconChainTypes> DataAvailabilityChecker<T> {
         self.da_check_required_for_epoch(epoch) && self.spec.is_peer_das_enabled_for_epoch(epoch)
     }
 
+    /// Determines if execution payload envelopes are required for an epoch (Gloas and later).
+    pub fn envelopes_required_for_epoch(&self, epoch: Epoch) -> bool {
+        self.spec.fork_name_at_epoch(epoch) >= ForkName::Gloas
+    }
+
     /// See `Self::blobs_required_for_epoch`
     fn blobs_required_for_block(&self, block: &SignedBeaconBlock<T::EthSpec>) -> bool {
         block.num_expected_blobs() > 0 && self.blobs_required_for_epoch(block.epoch())
diff --git a/beacon_node/beacon_processor/src/lib.rs b/beacon_node/beacon_processor/src/lib.rs
index ea87e9bc71..d2f7010854 100644
--- a/beacon_node/beacon_processor/src/lib.rs
+++ b/beacon_node/beacon_processor/src/lib.rs
@@ -417,6 +417,9 @@ pub enum Work<E: EthSpec> {
     RpcBlobs {
         process_fn: AsyncFn,
     },
+    RpcPayloadEnvelope {
+        process_fn: AsyncFn,
+    },
     RpcCustodyColumn(AsyncFn),
     ColumnReconstruction(AsyncFn),
     IgnoredRpcBlock {
@@ -483,6 +486,7 @@ pub enum WorkType {
     GossipLightClientOptimisticUpdate,
     RpcBlock,
     RpcBlobs,
+    RpcPayloadEnvelope,
     RpcCustodyColumn,
     ColumnReconstruction,
     IgnoredRpcBlock,
@@ -545,6 +549,7 @@ impl<E: EthSpec> Work<E> {
             Work::GossipProposerPreferences(_) => WorkType::GossipProposerPreferences,
             Work::RpcBlock { .. } => WorkType::RpcBlock,
             Work::RpcBlobs { .. } => WorkType::RpcBlobs,
+            Work::RpcPayloadEnvelope { .. } => WorkType::RpcPayloadEnvelope,
             Work::RpcCustodyColumn { .. } => WorkType::RpcCustodyColumn,
             Work::ColumnReconstruction(_) => WorkType::ColumnReconstruction,
             Work::IgnoredRpcBlock { .. } => WorkType::IgnoredRpcBlock,
@@ -1183,7 +1188,9 @@ impl<E: EthSpec> BeaconProcessor<E> {
                             Work::GossipLightClientOptimisticUpdate { .. } => work_queues
                                 .lc_gossip_optimistic_update_queue
                                 .push(work, work_id),
-                            Work::RpcBlock { .. } | Work::IgnoredRpcBlock { .. } => {
+                            Work::RpcBlock { .. }
+                            | Work::IgnoredRpcBlock { .. }
+                            | Work::RpcPayloadEnvelope { .. } => {
                                 work_queues.rpc_block_queue.push(work, work_id)
                             }
                             Work::RpcBlobs { .. } => work_queues.rpc_blob_queue.push(work, work_id),
@@ -1318,7 +1325,9 @@ impl<E: EthSpec> BeaconProcessor<E> {
                         WorkType::GossipLightClientOptimisticUpdate => {
                             work_queues.lc_gossip_optimistic_update_queue.len()
                         }
-                        WorkType::RpcBlock => work_queues.rpc_block_queue.len(),
+                        WorkType::RpcBlock | WorkType::RpcPayloadEnvelope => {
+                            work_queues.rpc_block_queue.len()
+                        }
                         WorkType::RpcBlobs | WorkType::IgnoredRpcBlock => {
                             work_queues.rpc_blob_queue.len()
                         }
@@ -1513,6 +1522,7 @@ impl<E: EthSpec> BeaconProcessor<E> {
                 beacon_block_root: _,
             }
             | Work::RpcBlobs { process_fn }
+            | Work::RpcPayloadEnvelope { process_fn }
             | Work::RpcCustodyColumn(process_fn)
             | Work::ColumnReconstruction(process_fn) => task_spawner.spawn_async(process_fn),
             Work::IgnoredRpcBlock { process_fn } => task_spawner.spawn_blocking(process_fn),
diff --git a/beacon_node/lighthouse_network/src/service/api_types.rs b/beacon_node/lighthouse_network/src/service/api_types.rs
index 486a443857..0b1d84b706 100644
--- a/beacon_node/lighthouse_network/src/service/api_types.rs
+++ b/beacon_node/lighthouse_network/src/service/api_types.rs
@@ -31,6 +31,10 @@ pub enum SyncRequestId {
     BlobsByRange(BlobsByRangeRequestId),
     /// Data columns by range request
     DataColumnsByRange(DataColumnsByRangeRequestId),
+    /// Request searching for an execution payload envelope given a block root.
+    SinglePayloadEnvelope { id: SingleLookupReqId },
+    /// Payload envelopes by range request
+    PayloadEnvelopesByRange(PayloadEnvelopesByRangeRequestId),
 }
 
 /// Request ID for data_columns_by_root requests. Block lookups do not issue this request directly.
@@ -76,6 +80,14 @@ pub enum DataColumnsByRangeRequester {
     CustodyBackfillSync(CustodyBackFillBatchRequestId),
 }
 
+#[derive(Debug, Hash, PartialEq, Eq, Clone, Copy)]
+pub struct PayloadEnvelopesByRangeRequestId {
+    /// Id to identify this attempt at a payload_envelopes_by_range request for `parent_request_id`
+    pub id: Id,
+    /// The Id of the overall By Range request for block components.
+    pub parent_request_id: ComponentsByRangeRequestId,
+}
+
 /// Block components by range request for range sync. Includes an ID for downstream consumers to
 /// handle retries and tie all their sub requests together.
 #[derive(Debug, Hash, PartialEq, Eq, Clone, Copy)]
@@ -252,6 +264,12 @@ macro_rules! impl_display {
 impl_display!(BlocksByRangeRequestId, "{}/{}", id, parent_request_id);
 impl_display!(BlobsByRangeRequestId, "{}/{}", id, parent_request_id);
 impl_display!(DataColumnsByRangeRequestId, "{}/{}", id, parent_request_id);
+impl_display!(
+    PayloadEnvelopesByRangeRequestId,
+    "{}/{}",
+    id,
+    parent_request_id
+);
 impl_display!(ComponentsByRangeRequestId, "{}/{}", id, requester);
 impl_display!(DataColumnsByRootRequestId, "{}/{}", id, requester);
 impl_display!(SingleLookupReqId, "{}/Lookup/{}", req_id, lookup_id);