Gas Fees and Cost Basis

Every transaction on Robinhood Chain pays a fee in ETH. The amounts are small, but they sit on almost every line of a tax report, and different countries handle them in different ways. This guide explains what a fee is made of, the common ways fees are treated for tax, and how PONSUM records them.

What a fee is made of

Robinhood Chain runs on Arbitrum Nitro. A transaction uses an amount of gas, and each unit of gas has a price. The fee is the gas used multiplied by the effective gas price, and it is paid in ETH by the wallet that sent the transaction.

Part of that gas pays for execution on Robinhood Chain itself, and part covers posting the transaction's data to Ethereum. Both are included in the gas your receipt reports, so the fee you see is the full amount that left your wallet. Gas prices on the chain have typically been around 0.01 to 0.3 gwei, which usually makes a fee a few cents or less.

Only the wallet that sends a transaction pays for it. If someone sends you tokens, the fee is theirs. If you interact with a contract, even in a transaction that fails, the fee is yours.

Common tax treatments

Tax rules usually look at why a fee was paid:

• Fees on a purchase are often added to the cost basis of what you bought, which reduces the gain when you later sell it.
• Fees on a sale are often deducted from the proceeds, which reduces the gain on that sale.
• Fees on a swap touch both sides, and countries differ on where they belong.
• Fees on everything else, such as token approvals, moves between your own wallets or failed transactions, may be deductible in some situations, may be added to the cost of the asset moved, or may not count at all.

Some countries add a second layer: the ETH you spend on a fee is itself a disposal of ETH. If your ETH has risen in value since you acquired it, even a tiny fee realizes a tiny gain. Across thousands of transactions, that can add up to a figure worth reporting.

Costs that are not gas

Some costs look like fees but never appear as gas. A Uniswap pool takes its fee out of the amount you swap, so it shows up as a slightly worse price rather than as a separate payment. A launchpad curve may take a trading fee inside the trade in the same way. These costs are already part of what you paid or received, and PONSUM records the amounts that actually moved, so they are reflected in your cost basis or proceeds without being counted twice.

Price impact works the same way. A large swap in a thin pool moves the price against you, and the difference is real money, but it is part of the trade price rather than a fee. That is one more reason the audit report shows the price source for every trade next to its fee.

How PONSUM records fees

For every transaction a workspace wallet sent, PONSUM reads the receipt and records the fee in ETH together with its USD value at the time. It then follows the default for the country you chose:

• Where the country's default counts fees in the calculation for a disposal, they are included in that disposal's gain or loss.
• Other fees are listed in the expenses report, so you can see them and decide what to do with them.

Every fee also appears in the audit report next to its transaction, and the portfolio view shows the total you have paid in fees.

Failed and invisible transactions

Some transactions cost gas but move no tokens: approvals, failed swaps and plain ETH sends. They leave no token transfer logs, and token transfer logs are how most of a wallet's history is imported, so a simple import would miss their fees completely.

PONSUM checks for this. It compares the number of transactions each wallet has sent with the ones the import found, and the current ETH balance with the balance the import explains. A gap in either becomes a Review item. You can paste the missing transaction hashes so they are imported exactly, add a manual entry, or accept the difference as an opening balance adjustment.

A worked example

These numbers are made up. You buy a token with USDG for $300 and pay a fee worth $0.04. Later you sell it for $500 and pay a fee worth $0.03.

• If both fees are counted, the cost becomes $300.04 and the proceeds $499.97, so the gain is $199.93.
• If the fees are ignored, the gain is $200.00.
• If the ETH used for the fees had doubled in value since you acquired it, some countries would also see two tiny gains on that ETH, each worth half of its fee.

For one trade the difference is trivial. For a busy wallet with thousands of transactions it can be real money, and it is exactly the kind of detail that is easy to get wrong by hand.

Practical tips

• Keep the ETH you use for gas in a wallet that belongs to your workspace, so the fees it pays are recorded.
• Clear transaction count gaps in Review, since they usually point to transactions whose fees are missing.
• Look through the expenses report at the end of the year, and ask your accountant which of those fees your country lets you use.
• Remember that the size of a fee does not decide its treatment: a fee of one cent follows the same rules as a fee of one dollar.

PONSUM is software, not tax advice. Check your local rules or ask an accountant.