IRS Crypto Warning Letters Explained: 6174, 6173, and CP2000

Got a warning letter from the IRS about your cryptocurrency? Don’t panic. 

Recently, more and more investors have reported receiving letters related to their cryptocurrency activity. In this guide, we’ll break down what you need about each warning letter (and what you should do to avoid further action from the IRS).

What is Letter 6174 for cryptocurrency? 

Letter 6174 is considered a no action letter, meaning it does not require a response. The letter should be considered a tap on the shoulder, not an accusation of underreporting. If you have met all the crypto tax filing obligations outlined in the letter, you have nothing to worry about. 

In most cases, you receive Letter 6174 if you are a known cryptocurrency investor. For example, the IRS may have received a 1099 form with your information from a cryptocurrency exchange, or you may have been identified in an exchange subpoena. 

If you’ve reported your cryptocurrency taxes accurately, no further action is required.

If you have not met all of your filing requirements, you should do so and amend any prior years tax returns that did not include your crypto-related gains, losses, and income.

What’s the difference between Letter 6174 and 6174-A? 

Letter 6174-A is a slightly more serious version of Letter 6174. While it doesn’t require a response, it means the IRS suspects you may have reported your income. 

If you receive this letter, you should double-check that you correctly reported your crypto taxes. You should also consider filing a crypto tax amendment for previous years.

What is Letter 6173 for crypto? 

Letter 6173 is more serious, and requires an immediate response. The IRS sends this letter if it has reason to believe you have underreported your crypto income. 

If you received Letter 6173, you have some options for responding:

1. Properly file the missing tax returning including your cryptocurrency transactions
2. Amend your prior years tax return if you did not properly report your cryptocurrency transactions
3. Or, if you believe you filed your cryptocurrency taxes correctly, respond to the IRS with a written letter explaining how you arrived at the income reported.

What is CP2000 for crypto? 

Letter CP2000 is considered the most serious warning letter for cryptocurrency, and is one step away from a full audit. You must respond within 30 days. 

The IRS sends CP2000 when the agency believes you have underreported your cryptocurrency income and has calculated your estimated tax payment. 

If you receive CP2000, you must amend your tax return or provide detailed records of your transactions to show that you accurately reported your taxes. 

‍Why is the IRS sending more warning letters? 

In 2025, investors reported receiving more crypto warning letters. It’s likely that this trend will continue in years to come. 

Starting in 2026, crypto exchanges will be required to report customers’ capital gains and losses via Form 1099-DA. These letters will lead to more warning letters being sent to customers (even if you’ve filed your tax return accurately!)