Base Mainnet Chain Stall
Affected: DepositsWithdrawalsBlock productionClient Software
Base Outage History
Base is up right nowBase had 27 outages in the last 2 years totaling 3700h 43m of downtime — averaging 1.1 incidents per month.
There were 27 Base outages since August 5, 2025 totaling 3700h 43m of downtime. Each is summarised below — incident details, duration, and resolution information.
Base Mainnet p2p peering stability
Affected: Client Software
Timeline · 3 updates
Base Mainnet Periodic Flashblocks Instability
Affected: Flashblocks
Timeline · 2 updates
- investigating Jun 02, 2026, 10:32 PM UTC
Our team is currently investigating degraded broadcasting of Flashblocks on Base mainnet. We believe TX inclusion in final blocks is not affected.
- resolved Jun 22, 2026, 04:35 PM UTC
The instability has been addressed and resolved. Node operators who were affected are recommended to upgrade to v1.1.1 of base/base which contains stability improvements and bug fixes: https://github.com/base/base/releases/tag/v1.1.1
Base Mainnet Withdrawal Delay
Affected: Withdrawals
Timeline · 2 updates
- identified May 29, 2026, 03:55 PM UTC
Base Mainnet withdrawals are delayed due to a TEE enclave issue that halted proposals. A fix is in progress.
- resolved May 31, 2026, 03:38 AM UTC
This incident has been resolved.
Delayed Transactions
Affected: Block production
Timeline · 2 updates
- investigating May 13, 2026, 04:44 PM UTC
Base is experiencing an elevated rate of missed blocks. Transactions sent during missed blocks are delayed until the next successful block.
- resolved May 14, 2026, 05:04 AM UTC
This incident has been resolved.
Elevated latency on Sepolia RPC
Affected: Public RPC API
Timeline · 3 updates
- identified May 10, 2026, 06:31 PM UTC
Latency on https://sepolia.base.org is high due to a node provider upgrade.
- monitoring May 10, 2026, 07:03 PM UTC
We have temporarily decreased rate limits for this endpoint to ease traffic. Latency is moving back to normal on this endpoint.
- resolved May 13, 2026, 04:52 PM UTC
This incident has been resolved.
Node Peering Stability on Base Testnet and Mainnet
Affected: Client SoftwareClient Software
Timeline · 2 updates
- monitoring Apr 30, 2026, 09:14 PM UTC
There is no outage. This is preemptive in case node operators encounter peering issues. However, upcoming p2p changes may impact peer discovery for Base nodes. If your node encounters p2p issues, please use the script linked here: https://gist.github.com/meyer9/8f15028681045062d59b7521deb19822#file-add-peers-sh
- resolved Jun 04, 2026, 07:42 PM UTC
The migration has been completed. It can be difficult to find a peer that isn't full on peers already. We are working with the Reth team to continue improving the ability to find peers.
Sepolia Testnet Unsafe Head Stalled
Affected: Block production
Timeline · 2 updates
- investigating Apr 16, 2026, 06:26 PM UTC
Base Sepolia Testnet is experiencing an outage in block production. The team is actively investigating.
- resolved Apr 16, 2026, 07:15 PM UTC
Block production has resumed on Sepolia testnet.
Sepolia safe head delayed
Affected: Withdrawals
Timeline · 2 updates
- investigating Apr 10, 2026, 10:54 PM UTC
We are currently investigating this issue. The Sepolia safe head is current stalled. This seems to affect op-node users running with consensus-layer sync mode.
- resolved Apr 11, 2026, 12:45 AM UTC
This is now mitigated. Safe head is progress normally for Sepolia Testnet
Sepolia Testnet: Flashblocks down
Affected: Flashblocks
Timeline · 2 updates
- identified Apr 07, 2026, 12:37 AM UTC
Flashblocks is currently down for Sepolia Testnet. The team has identified the issue and is rolling out a fix.
- resolved Apr 07, 2026, 12:55 AM UTC
This incident has been resolved.
Base Mainnet Flashblocks Degraded
Affected: Public RPC API
Timeline · 4 updates
- investigating Mar 24, 2026, 12:00 PM UTC
Base Mainnet is currently not producing flashblocks. Normal block production is unaffected. We're actively working to restore flashblock production.
- identified Mar 24, 2026, 01:55 PM UTC
We've identified an issue in our public RPC nodes that caused certain endpoints to not reflect latest flashblock data. Users may have also experienced increased error rates for read endpoints on https://mainnet.base.org/. We're working on implementing a fix.
- monitoring Mar 24, 2026, 03:16 PM UTC
A fix has been implemented and we are monitoring the results.
- resolved Apr 01, 2026, 01:41 PM UTC
This incident has been resolved.
Flashblock websocket connection errors
Affected: Public RPC API
Timeline · 3 updates
- investigating Mar 09, 2026, 08:29 PM UTC
Users connecting to the Flashblocks websocket (mainnet.flashblocks.base.org) may have trouble connecting and receiving flashblocks. Block production is unaffected. We are currently investigation the issue.
- monitoring Mar 09, 2026, 09:16 PM UTC
We are monitoring a fix that has been implemented.
- resolved Mar 09, 2026, 09:54 PM UTC
This incident has been resolved.
Sepolia block building issue
Affected: Block production
Timeline · 3 updates
- investigating Feb 18, 2026, 05:31 AM UTC
We are currently investigating the issue, blocks are being produced, but with no transaction included.
- monitoring Feb 18, 2026, 07:16 AM UTC
A fix has been implemented and we are monitoring the results.
- resolved Mar 10, 2026, 04:56 PM UTC
This incident has been resolved.
Transaction Inclusion Delays
Affected: Block productionTransaction pool
Timeline · 6 updates
High Rate of Transaction Drops and Transaction Inclusion Delays
Affected: Block production
Timeline · 6 updates
Periodically delayed block building on Base Mainnet
Timeline · 1 update
- resolved Jan 20, 2026, 03:51 PM UTC
Base mainnet is experiencing periodically delayed blocks due to volatile activity. We're actively monitoring and working to improve the consistency of block building performance. Between 14:45 and 15:10 UTC on 1/20/2026, users may have noticed delayed transaction inclusion and degraded block building performance .
Flashblocks Degraded Performance
Affected: Flashblocks
Timeline · 2 updates
- identified Nov 06, 2025, 09:58 PM UTC
We are aware of degraded Flashblocks building, resulting in fewer broadcasted Flashblocks than expected. Users may also experience periodic reorgs of Flashblocks.
- resolved Nov 12, 2025, 05:29 AM UTC
Flashblocks building performance has has returned to expected values.
Mainnet Flashblocks WebSocket Connection Instability
Affected: Flashblocks
Timeline · 3 updates
- investigating Nov 04, 2025, 03:32 PM UTC
We are currently investigating degraded connection stability to the Base Mainnet WebSocket endpoint for Flashblocks `wss://mainnet.flashblocks.base.org/ws`. Applications and nodes may experience intermittent connection drops to that endpoint.
- identified Nov 12, 2025, 05:38 AM UTC
We have identified bottlenecks with the Websocket endpoints distributing Flashblocks. Between Nov 5-10, several changes were made that reduced connection drops by 50%. However, investigation continues in order to further reduce connection instability and lower the latency in receiving messages. Updates will be posted here as progress is made.
- resolved Nov 17, 2025, 03:34 PM UTC
We have made improvements to the handling of rate limits in order to provide a more stable endpoint for Flashblocks.
Client bug causing inaccurate `eth_call` data on Flashblock endpoints
Affected: Flashblocks
Timeline · 3 updates
- identified Oct 29, 2025, 11:36 PM UTC
A bug is causing inaccurate data to be returned from `eth_call` requests when used on Flashblock RPCs. This happens only when the ‘pending’ tag is used for `eth_call`. We’re working on a base/node release to fix this as soon as possible.
- monitoring Oct 29, 2025, 11:53 PM UTC
A fix has been implemented and we are monitoring the results.
- resolved Oct 29, 2025, 11:57 PM UTC
This incident has been resolved.
High RPC latency and transaction inclusion times on Base Mainnet
Affected: Public RPC APIBlock production
Timeline · 2 updates
- identified Oct 20, 2025, 06:58 PM UTC
Base Mainnet is experiencing high RPC and transaction inclusion latencies, as well as periodic inconsistencies in block production times.
- resolved Oct 20, 2025, 09:07 PM UTC
Block building and RPC performance has returned to normal
Limited network capacity
Affected: Batch submissionBatch submissionBlock productionBlock production
Timeline · 3 updates
- investigating Oct 20, 2025, 08:23 AM UTC
We are investigating a reduction in Base network capacity.
- identified Oct 20, 2025, 08:39 AM UTC
AWS is having a major outage that is affecting Base infrastructure.
- resolved Oct 20, 2025, 09:50 AM UTC
The AWS outage has resolved. Batch submission has resumed, and transaction capacity has returned to normal.
Delayed Transaction Inclusion
Affected: Transaction pool
Timeline · 2 updates
- investigating Oct 17, 2025, 07:27 PM UTC
Periodic congestion on Base is causing delays in transaction inclusion.
- resolved Oct 18, 2025, 03:34 AM UTC
The mempool size has been increased to allow more transactions to be included in blocks quickly during periods of congestion. We will continue to monitor the network for delayed transaction inclusion.
Safe head delay from high transaction volume
Affected: Batch submission
Timeline · 3 updates
- identified Oct 10, 2025, 09:40 PM UTC
Heavy transaction volume on Base L2 is causing delays in batching data to Ethereum. Node operators may experience node client syncing delays and applications on Base may notice a lagging safe head. Block building (unsafe head) continues to function normally.
- identified Oct 10, 2025, 10:54 PM UTC
The safe head is still lagging behind, and the Base sequencing is currently limiting the amount of calldata it can include in L2 blocks. This is to ensure the safe head can progress on L1. Users may experience delays in transaction inclusion, and potentially a high rate of transaction drops.
- resolved Oct 11, 2025, 12:35 AM UTC
This incident has been resolved. Base chain is functioning properly.
Flashblocks Outage
Affected: Flashblocks
Timeline · 2 updates
- monitoring Sep 22, 2025, 12:02 AM UTC
Flashblocks were unavailable for ~10 minutes. We've identified the root cause and implemented a fix. We're currently monitoring the situation.
- resolved Sep 22, 2025, 12:37 AM UTC
This incident has been resolved.
Base Sepolia Preconf RPC Downtime
Affected: Public RPC API
Timeline · 3 updates
- identified Sep 11, 2025, 05:18 PM UTC
Base Sepolia Preconf Flashblocks RPC started experiencing downtime at 12:45pm ET. The issue has been identified and we are working to restore service.
- monitoring Sep 11, 2025, 05:32 PM UTC
A fix has been implemented and we are monitoring the results.
- resolved Sep 11, 2025, 06:03 PM UTC
The incident has been resolved.