Independent resource — not affiliated with Offchain Labs or the Arbitrum Foundation.

Arbitrum Tax Software Compared

Based on L2 bridge handling, GMX support, and user feedback from forums.

CoinLedger

Best for Arbitrum
  • Manual bridge merge tool — fix "Missing Cost Basis" warnings from bridge transactions
  • Arbitrum DeFi support — Uniswap, Camelot, Aave transactions tracked
  • Per-wallet cost basis — 2025 IRS requirement supported
  • No automatic GMX perpetuals (open/close position) tracking — like every tool we've checked, manual entry is still required
Try CoinLedger — code: CRYPTOTAX10 →

Also Strong: Awaken Tax

(Not an affiliate link)
  • Native support for 10,000+ DeFi protocols — including GMX perpetuals, which most tools struggle with
  • Best-in-class DeFi classification — automated transaction labeling praised as "night and day" vs Koinly by users
  • Proven at scale — CoinGecko case study: 25,000 users, $3B+ in assets tracked
Visit Awaken Tax →

Also Consider: Summ (formerly Crypto Tax Calculator)

  • Broad DeFi transaction classification (lending, borrowing, LP tracking) on Arbitrum
  • Strong overall reviews — ~4.6 on Trustpilot
  • Supports TurboTax, H&R Block, and international tax reports
Try Summ — code: DEFITAX20 →

Awaken Tax has the best GMX perpetuals support. Other tools may require manual review for complex trading.

Arbitrum Tax Issues to Know

ARB Airdrop

The March 2023 ARB airdrop was one of the largest ever (~$2B distributed). Taxable as ordinary income at fair market value when claimed. This becomes your cost basis for future sales.

Bridge Transactions

Bridging ETH to Arbitrum isn't taxable (you're moving, not disposing). But tax software often shows "Missing Cost Basis" — use CoinLedger's merge tool to fix this. Bridge fees are deductible.

GMX Trading

GMX perpetuals create complex tax scenarios with P&L, trading fees, and execution fees. No mainstream tax software automatically tracks perpetual open/close positions — users report needing manual tagging, including for GMX staking rewards (esGMX, ETH rewards), which are taxable income when received. The tax treatment of DeFi perpetuals more broadly remains unsettled (not Section 1256 contracts) — consult a tax professional. Separately, Koinly users have reported GMX on Arbitrum getting mislabeled as a different coin ("GameX") in an open forum thread — worth double-checking if you use Koinly.

Wallet Balance Tracking

A bug reported in January 2026 caused missing balances and USDC mixed up with bridged USDC.e on some Koinly-tracked Arbitrum wallets. Double-check your balances if you're on Koinly and hold both.

GMX V1 Exploit (July 2025)

A re-entrancy vulnerability drained roughly $40M from the GLP pool on Arbitrum on July 9, 2025. The attacker later returned the funds, keeping a $5M bounty. GLP holders affected by the incident may have theft-loss or recovery reporting questions — consult a tax professional before claiming a deduction.

ArbitrumDrip Season One

ArbitrumDrip Season One incentives ended February 17, 2026, distributing up to 24M ARB tokens to DeFi participants. These rewards are taxable as ordinary income at fair market value when received.

Per-Wallet Cost Basis (IRS Rev. Proc. 2024-28)

Universal cost-basis pooling across exchanges/wallets ended January 1, 2025 — the IRS now requires per-wallet (per-account) cost basis tracking. If you didn't make a safe-harbor allocation when the rule took effect, the deadline to do so is October 15, 2026. Consult a tax professional to confirm your allocation method is compliant.

Form 1099-DA Reporting

Exchanges are now issuing Form 1099-DA for tax year 2025, reporting digital asset proceeds directly to the IRS. Make sure the totals on your tax software reconcile with any 1099-DA you receive.

FAQ

Are Arbitrum bridge transactions taxable?

Generally no — bridging ETH from Ethereum to Arbitrum is moving assets, not disposing of them. However, bridge fees paid in ETH are deductible as transaction costs.

How is the ARB airdrop taxed?

The ARB airdrop is taxable as ordinary income at fair market value when claimed. This value becomes your cost basis. The March 2023 airdrop was valued at ~$1.20 per token at launch.

Are GMX perpetual trades taxable?

Yes. Each trade is a taxable event. Profits and losses are calculated based on your cost basis. No mainstream tax software automatically tracks GMX perpetual open/close positions, so manual tracking is typically needed. The broader tax treatment of DeFi perpetuals remains unsettled (not Section 1256 contracts) — consult a tax professional.

Can I deduct failed transaction fees?

Yes. Gas fees for failed transactions on Arbitrum are deductible as transaction costs, even though the transaction didn't complete.

Sources

Last updated: July 25, 2026