Your exchange hands you a tidy end-of-year report, the totals look clean, and it feels like the tax job is done. Then you remember the wallet you used for a DeFi experiment last spring, the coins you bridged to another chain, and the tokens still sitting on a platform you stopped logging into two years ago. The tidy report only ever covered part of the story.
This is the quiet problem with crypto taxes. Any single platform can only see the activity that happened on it. The moment your assets move between exchanges, wallets, or on-chain protocols, your history splits into pieces, and no one account holds the whole picture.
Why single-source reports get it wrong
A report from one exchange is accurate about that exchange and blind to everything else. That blind spot creates real problems at tax time:
Transfers look like sales: when you move coins from an exchange to your own wallet, the exchange often sees an outflow and nothing more. Left uncorrected, a transfer between your own accounts can be counted as a disposal you never made.
Cost basis goes missing: if you bought on one platform and sold on another, the selling platform has no idea what you originally paid. The gain it reports can be far higher than what you actually made.
Whole periods disappear: old wallets, delisted tokens, and closed accounts simply do not show up, so parts of your history are missing before you start.
None of this means you did anything wrong. It means the data was only ever half the picture, and half a picture is hard to file with confidence.
What getting it right actually takes
Accurate crypto tax reporting is less about the tax and more about the data. Three things make the difference:
- Bring every source together. Every exchange, wallet, and chain you have ever used, including the ones you would rather forget.
- Reconcile across them. Match transfers to their other side, carry cost basis with the asset wherever it moves, and rebuild a single continuous history.
- Check for gaps before you file. Surface missing accounts, inconsistent balances, and unexplained periods while there is still time to fix them.
How Summ does it
Summ is built for exactly this. Its reconciliation engine tracks transactions across 3,500+ exchanges, wallets, and blockchains, with deep on-chain coverage spanning DeFi, DEXs, NFTs, and complex protocols. By pulling every source into one place and reconciling across them, Summ rebuilds your complete history rather than a slice of it.
From there it does the checking for you: flagging likely wallets or exchanges missing from your data, surfacing gaps and inconsistencies, and prioritising the issues that actually move your tax position. The result is a clear, explainable report that you can stand behind if questions ever arise. And Summ is read-only, so it can see your transaction history but can never move, trade, or touch your assets.
Getting started as an Abarai user
Connect your Abarai account along with every other exchange and wallet you use, let Summ reconcile the full history, and generate a report built on validated data. As an Abarai user you get 20% off when you sign up. See the full picture before you file.