Errors in CoinTracking, Koinly, and others: how to fix them in 2025

Executive Summary: Thousands of users reach the tax season with the same nightmare: CoinTracking or Koinly import their transactions, but the figures DO NOT add up. Negative balances, invented income, misinterpreted swaps, duplicated transactions, or complete gaps in chains like BNB Chain, Polygon, or Solana.

This guide analyzes why this happens, what mistakes taxpayers make, what tax risks they face, and how to identify them before it is too late. It also explains how IN DIEM & Cryptoveritas 360 correct these errors professionally so that your report remains clean, traceable, and tax-secure.

Table of Contents

1. Introduction: the false “everything is fine”
2. Why CoinTracking and Koinly fail in 2025
3. Total Chaos (Case 1) and Discrepancies (Case 2): two profiles, same result: error
4. Common technical errors
5. Real tax risks
6. How to detect the failure
7. What the user does wrong
8. How we fix it professionally
9. Case study
10. How we help you
11. Technical glossary

1. Introduction: the false “everything is fine”

Every year the same scene repeats itself. The user believes everything is ready: they download the CSVs from the exchange, upload them to CoinTracking or Koinly and… magic: a perfect automatic report appears.

Until they look at the balances. And then comes the surprise:

• Tokens they never owned.
• Non-existent losses.
• Gains they never obtained.
• Swaps converted into sales.
• Hundreds of movements without date, pair, or price.

The feeling is always the same: “I thought everything was fine… until I tried to make it add up.”

Welcome to the part nobody explains to you: the software is not the problem, it is the information it receives.

2. Why CoinTracking and Koinly fail in 2025

The main reasons:

3. Total Chaos (Case 1) and Discrepancies (Case 2): two profiles, same result: error

This may be your case. 3 exchanges, few operations, but:

• Missing price history at certain times.
• Duplicated operations.
• Airdrops interpreted as ordinary income.
• Incorrectly recorded staking.
• Deposits labeled as purchases.
• Withdrawals detected as sales.

Result: CoinTracking, Koinly, or any other tool generates incorrect balances… and you do not know where the error is. We solve it through the CryptoTax Start service.

4. Common technical errors we see every day

These are the most common errors in CoinTracking and Koinly in 2025:

🔴 Error 1: Corrupt or incomplete CSVs: More than half of the CSVs from Binance, Crypto.com, Coinbase, Bitget, or KuCoin arrive with:

• Lack of historical prices.
• Swapped columns.
• Duplicates.
• Missing intermediate trades.
• Deposits without origin, interpreted as purchases.

🔴 Error 2: Misinterpreted swaps: An ETH → USDC swap on Uniswap can generate:

• 1 trade,
• 4 trades,
• or literally nothing,

depending on how the explorer interprets it.

🔴 Error 3: Staking treated as “income”: Very serious for the Tax Agency. Not all staking is taxed the same. Koinly and CoinTracking inflate it by default if not reviewed.

🔴 Error 4: Phantom losses: The software detects supposed losses generated by:

• Internal movements.
• Chain changes.
• Bridges.
• Transfers between own wallets.

🔴 Error 5: Negative balances: The definitive symptom of structural failure. If a negative balance appears, the tool is telling you: “I do not have enough information to reconstruct your history.”

5. Real tax risks

• Invented gains → you overpay; Your IRPF will include profits you never had, with the resulting tax overcost.

• Non-existent losses → possible fraud due to oversight: The Tax Agency may interpret it as a maneuver to artificially reduce the tax liability.

• Misclassified capital yields: Staking and CeFi products are a headache if reported incorrectly, both in type of income and tax base.

• Fines for inaccurate data: If the report is not traceable and is requested in an inspection, you will not be able to justify it with legal certainty.

5. Risk of supplementary assessment

When the inspector sees inconsistencies, it opens the door to a supplementary assessment and a much more aggressive review.

6. How to detect the failure (without being an expert)

If just one of these signs occurs, your report is WRONG:

• Negative balances.
• Invented tokens.
• Income you do not recognize.
• Deposits without a clear origin.
• Withdrawals without a destination.
• Impossible variations in stablecoins.
• Partial lack of operations.
• Trades without a counterpart.

If you detect it, you must stop. Continuing to fill out the IRPF with corrupt data is a ticking time bomb.

7. What the user does ❌ (wrong), to be clear…

• Believing that CoinTracking/Koinly “does it alone”: No. They need perfect data and subsequent validation.

• Believing their CSV is fine because the exchange provided it: The CSV is not a tax document; it is a technical statement. It can be wrong, incomplete, or missing critical fields.

• Not validating operations one by one: Basic inconsistencies must be checked: balances, number of operations, types of movement, etc.

• Not using explorers to reconstruct gaps: Software DOES NOT read on-chain data completely in all networks and cases. They require manual support.

• Mixing chain IDs and bridged tokens: Classic confusion: USDC (Ethereum) ≠ USDC (Polygon) ≠ USDC (Base). For traceability purposes, they are not the same.

• Not labeling special operations: Airdrops, forks, bonuses, rebases… require specific technical-tax treatment, which the user often does not configure.

8. How we solve it at IN DIEM (2025 Method)

This is our professional approach:

1) CSV Audit: We validate integrity, consistency, duplicates, and the absence of critical fields.

2) Manual reconstruction: We use explorers (Etherscan, Basescan, Solscan, etc.) to reconstruct operations that the CSV or software do not capture correctly.

3) Tax interpretation: We classify operations according to Spanish tax regulations (IRPF), preventing the software from simplifying where it should not.

4) Staking cleanup: We recalculate real yields. We eliminate fictitious or misassigned interest.

5) Full traceability: Every token, every movement, and every chain is explained with economic and tax sense.

6) Final report for the Tax Agency: We prepare a report ready to be defended before the Administration, if necessary.

9. Narrative case study

Real user (Case 2): 3 exchanges, 480 total operations. Uploads CSVs to Koinly.

The result:

• More than €12,000 in invented gains.
• 41 deposits without origin.
• 18 withdrawals interpreted as sales.
• 3 duplicated tokens due to bridging errors.
• -2.3 ETH phantom balance.

Solution:

• We corrected the CSVs.
• We relabeled problematic swaps.
• We reconstructed incomplete history from 2021.
• We eliminated duplicates.
• We rectified the staking treatment.

Final balance: everything adds up. IRPF filed without risks. And the user is sleeping soundly.

10. How we help you

Recommended service: CryptoTax Start

Perfect for cases of discrepancies ( Case 2) (“appears correct, but…”), when the CSV seems clean but the data explodes upon import.

What we do for you

• CSV debugging.
• Duplicate removal.
• Relabeling of basic swaps.
• Correction of false income.
• Basic reconstruction with explorers.
• IRPF report ready to file.
• Manual review by a crypto tax expert.

Where we operate. International Service.

We prepare crypto tax reports for any country in the world, regardless of exchanges, jurisdiction, or complexity of operations.

Our service is fully international because crypto taxation is not based on borders, but on blockchain traceability, and that is precisely our strength: we analyze wallets, DEXs, CEXs, bridges, swaps, and on-chain movements with technical criteria that apply equally in Spain, Latin America, the United States, or the European Union.

Thanks to our blockchain forensics methodology, history reconstruction, and universal tax classification (based on OECD standards and comparative regulations), we can prepare valid, consistent, and defensible reports before any tax authority on the planet. In short: wherever your wallet operates, we have you covered.

👉 Hire CryptoTax Start and we will make your crypto tax report perfect for your IRPF.
👉 Professional diagnosis in 24–48h.

11. Technical glossary

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Experts in New Technologies and Crypto Assets

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In an increasingly complex and competitive regulatory environment, having a firm that understands both technology and the law is key to minimizing risks and seizing opportunities. In Diem Abogados, in collaboration with its technological partner Cryptoveritas 360, does not just advise: it accompanies, implements, and ensures that your crypto company complies with regulations, integrates secure technological solutions, and prospers in the digital ecosystem.

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