ETH gas fee calculator: how much have you spent this tax year?
Paste a wallet address. We add up the gas paid this UK tax year on Ethereum, Arbitrum, Optimism, Base, or Polygon, then show you how much of it is deductible against your capital gains under HMRC Section 38.
For informational purposes only. Not tax advice. Figures are approximate.
HMRC: which of this gas is deductible?
Gas on disposals is deductible. Section 38 TCGA 1992 treats gas paid on a sale or swap as an "incidental cost of disposal", so it reduces the disposal proceeds, which reduces your capital gain.
Gas on acquisitions adjusts the cost basis. Gas paid when you bought or received a token gets added to that token's Section 104 pool cost, so you get the deduction later, when you eventually sell.
Gas on transfers is NOT deductible. Sending crypto between your own wallets is not a disposal, so the gas has no acquisition or disposal to attach to. HMRC has been consistent on this in the Cryptoassets Manual.
This tool shows your total outbound gas. ChainTax separates disposal-gas from transfer-gas automatically when you connect for a full report. That's the figure that lands on SA108.
See your deductible-vs-non-deductible breakdown
This tool sums every outbound transaction. ChainTax sorts each one into deductible disposal gas, basis-adjusted acquisition gas, and non-deductible transfer gas, the breakdown HMRC expects on your SA108.