Why Your Transaction Is Stuck on Pending And How to Fix It (Step-by-Step)

1) How fees & nonces work (90-second refresher)

On Ethereum and most EVM chains, every account’s transactions are numbered with a nonce starting at 0. The network processes them in order. If nonce 12 is pending, then nonce 13 and above cannot be mined until 12 is mined or replaced. That’s how nonce locks happen.

Since EIP-1559, you set a maxFeePerGas (ceiling) and a maxPriorityFeePerGas (tip). Your actual price paid is roughly baseFee + priority. If you underbid, miners/validators ignore you until demand cools.

Takeaway: Always fix the oldest pending transaction first. Increasing the fee on a newer nonce does nothing while an older nonce is blocking the pipeline.

2) Diagnose in 5 minutes (checklist)

1. Find your tx on an official explorer. Use Etherscan (Ethereum), Arbiscan (Arbitrum), BaseScan (Base), etc. Paste the hash from your wallet’s activity tab.
2. Check current gas range. Compare your maxFee and priority to live suggestions (e.g., Gas Tracker). If your priority is below current, you’re likely underbidding.
3. Look for “dropped & replaced.” If the explorer says “replaced,” your wallet may still show pending due to cache/RPC. Refresh, change RPC, or reimport account.
4. Check your account nonce. On the explorer’s address page, note the “next nonce.” If your pending tx has a lower nonce, all later ones will queue behind it.
5. Ask: would this tx revert? Swaps with too-tight slippage, approvals to bad routers, or insufficient token balances will never succeed, miners ignore them if underpriced; if mined, they may revert and still burn gas.
6. Check RPC/Wallet health. If explorer shows a different state from your wallet, your RPC might be lagging. Switch RPC provider (Infura, Alchemy, Ankr, QuickNode) or toggle airplane mode to force refresh.

Heads-up: During extreme congestion (popular mints, airdrops), fees can spike for minutes to hours. Underpriced txs sit pending until the market calms or until you replace them.

3) Fixes by scenario (Speed Up, Cancel, Replace)

4) Wallet-specific guides

5) Rollups & bridges: pending vs withdrawal delay

On Optimistic rollups (Base, Arbitrum, OP Mainnet), withdrawals to L1 can take days due to challenge windows. That’s not “pending” in the mempool, it’s an enforced delay by design. Deposits are typically fast; withdrawals wait for fraud-proof windows to pass.

Use official bridges first: Base docs, Arbitrum docs, OP docs. Third-party bridges can offer “fast exits” by lending you funds on L1 immediately at a fee and smart-contract risk.

6) Account Abstraction (EIP-4337): pending UserOperations

With smart wallets using EIP-4337, you submit UserOperations to a bundler, which then posts them to an EntryPoint contract. If your UserOp is “pending,” the cause can be:

• Paymaster issues: the gas sponsor is out of quota or rejects your policy, increase your own gas limit/fee or switch paymasters.
• Simulation failure: the UserOp doesn’t pass validation (e.g., session policy), so bundlers won’t include it.
• Bundler/RPC visibility: your wallet’s bundler is down. Switch provider or retry later.

Check your wallet’s activity and the EntryPoint logs; many AA wallets expose “why validation failed.” If in doubt, re-submit with a higher max fee or temporarily disable paymaster.

Learn more: EIP-4337.

7) Dev & power-user CLI recipes

Check nonce & pending status (ethers.js)

import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider(process.env.RPC_URL);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);

const main = async () => {
  const nonceLatest = await provider.getTransactionCount(wallet.address, "latest");
  const noncePending = await provider.getTransactionCount(wallet.address, "pending");
  console.log({ nonceLatest, noncePending }); // pending may be > latest if you have queued txs
};
main();

Replace (Speed Up) with higher tip (viem)

import { createWalletClient, http, parseEther } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { mainnet } from "viem/chains";

const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const client = createWalletClient({ account, chain: mainnet, transport: http(process.env.RPC_URL) });

const replaceTx = async (nonce, to, data = "0x") => {
  const fee = await client.estimateFeesPerGas(); // EIP-1559 { maxFeePerGas, maxPriorityFeePerGas }
  // bump priority by ~1-2 gwei above suggested fast range (tune as needed)
  const maxPriorityFeePerGas = (fee.maxPriorityFeePerGas ?? 1n * 10n**9n) + 2n * 10n**9n;
  const maxFeePerGas = (fee.maxFeePerGas ?? 30n * 10n**9n) + 5n * 10n**9n;
  return client.sendTransaction({ to, data, value: 0n, nonce, maxPriorityFeePerGas, maxFeePerGas });
};

// Example: cancel self with same nonce
// await replaceTx(12, "0xYourAddressHere");

Foundry one-liner: cancel nonce with 0-ETH self-tx

# Replace & cancel nonce N
cast send 0xYourAddress --value 0 --nonce N \
  --priority-gas-price 3gwei --gas-price 0 \
  --eip1559 --max-fee-per-gas 40gwei --private-key $PRIVATE_KEY \
  --rpc-url $RPC_URL

Why “Dropped & Replaced” still looks pending in my wallet?

Your local wallet cache or RPC may not have updated. Force refresh: change RPC endpoint, reload the extension/mobile app, or reimport the account (seed securely backed up).

8) Prevention playbook

• Use EIP-1559 smart settings. Let your wallet auto-suggest ranges, then nudge the tip slightly higher if you need fast inclusion.
• Check gas before sending. Peek at the gas tracker or your L2’s explorer. During spikes, either wait or pay to cut the line.
• Avoid multiple “send spams.” Don’t fire 5 swaps in a row, if nonce 1 stalls, nonces 2–5 are stuck too.
• Simulate first. Many wallets/dapps simulate calls (tenderly, block explorers). If simulation fails, fix inputs before paying gas.
• Keep RPC options handy. Add 2–3 reputable endpoints; if one lags, switch.
• Learn the buttons. Practice Speed Up and Cancel with tiny amounts so you’re calm when fees spike for real.
• For devs: implement nonceManager and backoff logic; don’t queue many nonces blindly.

9) FAQ (myths & edge cases)

10) External docs & references

Recap

• Pending is usually fees (underbid), nonce order, RPC desync, or a tx that would revert.
• Fix the oldest pending tx: Speed Up or Cancel with the same nonce and a higher tip.
• Verify on an official explorer; don’t trust only the wallet UI.
• On rollups, withdrawal delays are expected, not mempool pending.
• Prevent repeats: simulate, watch gas, avoid spam queuing, and practice the buttons with tiny amounts.

Need hands-on help unblocking a specific transaction (hash, network, wallet)?