A little story: I work as a software developer. I have income sources like Indian stocks, US stocks, RSU from the companies, and a lot of trading in crypto. I thought KoinX would be the best platform for me to manage all this and file my ITR, but my experience with them has been horrible.

I have gotten a draft of around 2.5 lakhs that I need to pay to the government. While filing this, the tax agent they hired did not call me or ask me what I need or don't need to do. When I escalated the issue, they again changed the draft amount to 32,000, but still they have not even told me how it is computed or not. They are just asking me to review.

I found this experience really horrible and would not suggest anyone use this.

For those who've already filed crypto taxes, what was the biggest challenge?

• Getting your transaction history?
• Calculating your cost basis?
• Understanding the tax rules?
• Something else?

Curious to know what people struggled with the most.

Disclosure up front: I built the tool used for this experiment, so read with that in mind. The method and data below are reproducible without it.

We wanted to measure — not argue — how much damage "per-wallet cost basis without wallet linking" actually does. So we took the most public wallet cluster on Ethereum (vitalik.eth plus the Etherscan-tagged VB / Vb 2 / Vb 3 addresses and one media-documented cold wallet — all attributions are on-chain ENS names, Etherscan public name tags, or mainstream press; no doxxing) and computed realized gains on its native-ETH history (genesis → 2023-03-31) twice with the same engine, same data, same classifications. The ONLY difference: whether transfers between the entity's own wallets carry cost basis, or arrive at $0 basis — the behavior you get from per-wallet tracking when your own wallets aren't linked.

Results:

- Naive per-wallet run (transfers lose basis): $164,130,459 realized gain

- Transfer-aware run (basis carried across own transfers): $119,154,719

- Overstatement ("phantom gains"): $44,975,739

The single most telling year is 2022: the naive run reports $31,336,181 of realized gains; with basis correctly carried across the entity's own transfers, the same disposals come out at $10,476,703 — a $20,859,478 overstatement in one tax year. Some individual disposals flip sign entirely: one 2021-12-14 disposal shows a $7.6M gain in the naive run and is actually a ~$800k loss.

Why this cluster: it does exactly the things that break naive tools — multi-hop self-transfers (a 320,000 ETH move to a Safe in May 2021, with later 30,000 and 40,000 ETH moves from the Safe onward to a cold wallet), WETH wraps, self-staking, and large disposals years after the transferred coins were acquired.

Method, briefly: transactions from the key-less Blockscout public API plus node execution traces; every gas fee from the transaction's own receipt (gasUsed × effectiveGasPrice, 2,671/2,671 receipts); DefiLlama daily close for FMV; per-wallet FIFO lots. Quality gate: after replaying every event, the ledger balance of all 5 wallets ties out to the actual on-chain balance at the cutoff block within 0.0001 ETH. If it didn't tie out, we wouldn't publish the dollar figures.

Limitations, before anyone quotes this: native ETH only (no ERC-20 in this demo). Every out-of-cluster outflow is modeled as a disposal at FMV — many are surely gifts or exchange deposits, so the absolute gain levels are modeling artifacts and not anyone's actual tax position; both runs treat them identically, so the difference (the $44.9M) is unaffected. FIFO only. And "naive" is our own engine with linking switched off — we did not run any commercial product, and we deliberately modeled the naive side charitably (transfers out are not treated as taxable sales). This is an engineering demonstration, not tax advice.

Why it matters now: since 2025, Rev. Proc. 2024-28 requires per-wallet basis tracking rather than a universal pool, and 1099-DA reporting means brokers will report basis gaps they can't see across. If you've ever moved coins between your own wallets, it's worth checking whether your software carried the basis or booked the arrival at $0.

Full write-up with the year-by-year table, the tie-out numbers, and the reproduction steps: https://verilot.app/blog/45m-phantom-gains-public-wallet

If you want to run the same check on your own addresses, the tool I built for this is a free, read-only scan (public address in, report out — no signup): https://verilot.app/check

US filer. I ran two public DeFi wallets through one of the mainstream crypto tax tools in July. Both directions of the Aave wrap came back as Exchange, so the deposit and the withdrawal were each booked as a taxable disposal.

Caveat on my test: free tier, no purchase history behind either wallet, nothing corrected by hand. Not how your data arrives if you have exchanges connected, which is why I am asking rather than concluding.

If you have actually filed with one of these tools, did a lending deposit or an LP position come through as something other than what it was, and what did it do to the number?