📝 Description

Each uncorrected warning in Waltio directly impacts your tax calculation. The impact depends on the computation method applicable in your country. This article explains the fiscal consequences of not correcting each type of warning, based on your computation method.

⚠️ The 3 types of warnings

Waltio generates 3 types of warnings when analysing your transactions:

Negative balance — Your stock of a cryptocurrency on a platform drops below 0 at some point.
Missing price — A token has no known market price. Waltio uses a default price of 0 EUR.
Transaction to categorise — A deposit or withdrawal has no label. Waltio applies a default behaviour that can alter your calculation.

:scales: Average cost methods (pooled)

These methods calculate a global average cost for your entire portfolio. Each unit of the same crypto has the same acquisition price. The impact of an individual error is diluted across the entire portfolio.

WAC (Weighted Average Cost)

How it works: The TPA (Total Portfolio Acquisition price) represents the total cost of all your crypto. The capital gain upon sale is calculated with the formula:

Capital gain = Sale price - (TPA × Sale price / TPV)

Where TPV = Total Portfolio Value at the time of sale.

Countries: France

Impact of warnings:

Warning	Impact on WAC	Consequence
Negative balance	The TPV is distorted downwards because crypto is missing from the stock. The fraction deducted from the TPA is larger.	Capital gain lower than reality. Risk of under-declaration.
Missing price	A token valued at 0 EUR reduces the TPV. Example: if the BTC price is missing and you hold 1 BTC worth 50,000 EUR, your TPV loses 50,000 EUR.	Capital gain lower than reality. Risk of under-declaration.
Unlabelled deposit	The default AP is 0 EUR. In France, passive gains have an AP of 0 EUR by default.	Limited impact — this is the expected behaviour for passive gains.
Unlabelled withdrawal	The withdrawal is treated as a portfolio exit.	Variable impact depending on the actual nature of the withdrawal.

👉 Transfers between accounts: With WAC, the AP of an individual deposit has little influence on the final calculation because the cost is averaged across the entire portfolio. The "Transfer between accounts" label is still recommended but its absence is less critical than with FIFO/LIFO.

ACB (Adjusted Cost Base)

How it works: The adjusted cost base represents the total cost of all your units of a given crypto, divided by the total number of units. The capital gain upon sale is calculated with the formula:

Capital gain = Sale price - (ACB per unit × number of units sold)

The ACB is adjusted with every purchase, sale, or event that modifies the cost (fees, returns of capital, etc.).

Countries: Austria, Brazil, Japan, Romania, Sweden

Impact of warnings:

Warning	Impact on ACB	Consequence
Negative balance	Missing purchases reduce the total cost. The ACB per unit is lower than reality.	Capital gain higher than reality upon resale. Risk of over-taxation.
Missing price	A token valued at 0 EUR reduces the ACB per unit to 0 for that lot.	The entire sale price is considered a gain. Over-taxation.
Unlabelled deposit	The default AP depends on the country configuration.	The deposit may not be correctly categorised for tax purposes.
Unlabelled withdrawal	The withdrawal may trigger an exit from the ACB pool.	The ACB is adjusted accordingly, which distorts subsequent calculations.

👉 Transfers between accounts: Like WAC, ACB is an average cost method. The "Transfer between accounts" label is still recommended but its absence is less critical than with FIFO/LIFO. However, a mislabelled transfer can distort the number of units in the pool, which changes the ACB per unit.

:scales: Sequential methods (per lot)

These methods assign an individual acquisition price to each lot of crypto. The order of purchase determines which lot is sold first. The impact of an error is direct and immediate on the calculation of the next sale.

FIFO (First In, First Out)

How it works: The first crypto purchased is the first sold. Each lot keeps its own AP. Upon sale, the AP of the oldest lot is used.

Countries (FIFO Universal): Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Egypt, Estonia, Finland, Germany, Greece, Hungary, Iceland, India, Indonesia, Ireland, Kenya, Latvia, Lithuania, Mexico, Morocco, Norway, Poland, Portugal, Slovakia, Slovenia, South Korea, Spain, Turkey, Ukraine, Vietnam

Countries (FIFO Per Wallet): United States

👉 In the United States, recent IRS broker regulations mandate per-wallet tracking instead of universal pooling. Impact of warnings:

Warning	Impact on FIFO	Consequence
Negative balance	The FIFO queue is incomplete: the missing earliest purchases distort the exit order. The AP of subsequent sales is incorrect.	Capital gain unpredictable — can be overestimated or underestimated.
Missing price	The AP of this FIFO lot is 0 EUR. Upon resale, the entire sale price is considered a gain.	Over-taxation, direct and immediate.
Unlabelled deposit	The default AP varies by country (see below). The passive income will not be correctly categorised for tax purposes.	Distorted calculation and/or incomplete declaration.
Unlabelled withdrawal	Without a label, Waltio does not know if this is a transfer (not taxable), a swap (potentially taxable), a payment, etc.	A non-taxable withdrawal (e.g. transfer to a Ledger) may be treated as a taxable event, or vice versa.

Default AP of an unlabelled deposit (FIFO):

Default AP	Countries	Consequence
0 EUR	Germany	Artificially inflated capital gain. Passive income not declared as "Sonstige Einkünfte" (Section 22 No. 3 EStG).
Market price	Belgium, Spain	The AP is correct, but the passive income is not correctly categorised for tax purposes (investment income, savings base, etc.).

⚠️ Correctly labelled deposit but AP at 0 EUR

Even if you have correctly labelled a deposit (e.g. "Masternodes & staking"), Waltio may not know the token price at the time of reception. In this case, the AP will be 0 EUR even though the label is correct.

This is a common pitfall: you think everything is in order, but the calculation is still distorted. It is therefore essential to check the prices of your deposits in the "Missing price" tab, even for transactions that are already labelled.

LIFO (Last In, First Out)

How it works: The last crypto purchased is the first sold. Each lot keeps its own AP. Upon sale, the AP of the most recent lot is used.

Countries: Italy

Impact of warnings:

Warning	Impact on LIFO	Consequence
Negative balance	The LIFO stack is corrupted: missing recent purchases directly change the AP of the next sale.	Unpredictable impact on the calculation. The IVAFE wealth tax (0.2%) is also distorted because the portfolio value on 31 December is incorrect.
Missing price	The AP of this LIFO lot is 0 EUR. The capital gain will be 100% of the sale price.	Over-taxation, direct, taxed at 26%.
Unlabelled deposit	The default AP is 0 EUR. For passive gains (staking, airdrops), this is correct. But if the deposit is actually a transfer between accounts, the AP should inherit the original AP — not be 0 EUR.	Severe impact if not a passive gain: with LIFO, each lot has its own AP. An AP of 0 EUR on a transfer directly distorts the calculation of the next sale.
Unlabelled withdrawal	Without a label, Waltio does not know if this is a transfer (not taxable), a swap (potentially taxable), a payment, etc.	A non-taxable withdrawal (e.g. transfer to a Ledger) may be treated as a taxable event, or vice versa.

⚠️ Correctly labelled deposit but AP at 0 EUR

As with FIFO, even if you have correctly labelled a deposit, Waltio may not know the token price at the time of reception. The AP will then be 0 EUR despite a correct label. Check the prices of your deposits in the "Missing price" tab, even for transactions that are already labelled.

⚠️ Transfers between accounts with FIFO / LIFO

A transfer between accounts is when you move your crypto from one platform to another without selling it. For example: sending ETH from Binance to your Ledger, or from Metamask to Bitget. You remain the owner of the same crypto — only the location changes.

This is very different from a sale (swap, payment, conversion to fiat), where you dispose of your crypto and potentially trigger a taxable event.

With both FIFO and LIFO, the "Transfer between accounts" label is critical because each lot has its own AP. Without this label, Waltio does not know that this deposit corresponds to a withdrawal already made elsewhere, and the AP will not be correctly carried over.

Rule: Always label both the deposit AND the withdrawal as "Transfer between accounts" when the two transactions are linked.

Situation	Deposit AP (FIFO/LIFO, default = 0 EUR)	Deposit AP (FIFO, default = market price)	Fiscal impact
Deposit + withdrawal correctly linked and labelled	Original AP of the crypto	Original AP of the crypto	Correct calculation
Deposit without "Transfer between accounts" label	0 EUR	Market price at the time of deposit	Default = 0 EUR: over-taxation (AP drops to 0, the entire sale price is considered a gain). Default = market price: distorted calculation as market price replaces the original AP (over-taxation if the crypto lost value, under-taxation if it gained value).
Deposit labelled "Transfer between accounts" without a matching withdrawal	0 EUR	0 EUR	Silent error: no negative balance (stock is correct), but the AP is 0 EUR because there is no withdrawal to inherit the AP from. The calculation is distorted without any visible warning.

Example: You buy 1 ETH at 2,000 EUR on Binance and transfer it to your Ledger.

Correct: The Binance withdrawal and Ledger deposit are linked. The AP of the ETH on Ledger remains 2,000 EUR.
Deposit without label (default = 0 EUR): The AP of the ETH on Ledger is 0 EUR. If you sell 1 ETH at 3,000 EUR, Waltio calculates a gain of 3,000 EUR instead of 1,000 EUR.
Deposit without label (default = market price): The AP of the ETH on Ledger is 2,500 EUR (market price) instead of 2,000 EUR (original AP). If you sell 1 ETH at 3,000 EUR, Waltio calculates a gain of 500 EUR instead of 1,000 EUR.
Deposit labelled "Transfer" without a matching withdrawal: The AP is 0 EUR. No negative balance, no warning. But the calculated gain will be 3,000 EUR instead of 1,000 EUR.

⚖ Special case: Wealth Tax

Some countries do not tax crypto capital gains in the same way. They apply a wealth tax based on the total portfolio value at a given date, rather than tracking capital gains per transaction.

Countries: Netherlands, Switzerland

Netherlands: The "Box 3" system taxes the total value of your portfolio on 1 January of the year. Waltio still needs to use a computation method to value the portfolio — warnings therefore impact the declared value.
Switzerland: Cantons apply a cantonal wealth tax based on the portfolio value at year-end. Capital gains are generally tax-free for private investors, but the portfolio value must be correct.

Impact of warnings:

Warning	Impact	Consequence
Negative balance	The portfolio value is distorted.	Incorrect wealth declaration.
Missing price	A token valued at 0 EUR reduces the portfolio value.	Under-declaration of wealth.
Unlabelled deposit/withdrawal	The crypto stock may be incorrect.	Portfolio value distorted at the reference date.

💡 Summary table by method

Aspect	WAC	ACB	FIFO	LIFO	Wealth Tax
Principle	Global average cost	Adjusted cost base per unit	First purchased, first sold	Last purchased, first sold	Portfolio value at date
AP per lot	No (average)	No (average)	Yes	Yes	Not applicable
Sensitivity to "Transfer" label	Low	Low	Critical	Critical	Moderate
Impact of a missing price	Reduces TPV → under-declaration	Reduces ACB → over-taxation	AP = 0 → over-taxation	AP = 0 → over-taxation	Wealth undervalued
Impact of a negative balance	Reduces TPV → under-declaration	Reduces ACB → over-taxation	Queue corrupted → unpredictable	Stack corrupted → unpredictable	Wealth undervalued
Countries	France	Japan, Romania, Sweden	Belgium, Germany, Spain, USA, + 25 countries	Italy	Netherlands, Switzerland

💡 Recommendations

Correct all warnings before generating your tax documents.
Priority: start with negative balances, then missing prices, then transactions to categorise.
FIFO/LIFO: systematically label both the deposit AND the withdrawal for transfers between accounts (e.g. Binance to Ledger, Metamask to Bitget).
Missing prices: use CoinGecko to find the daily average price.
Consult the label articles specific to your country to identify the correct label to apply.