CoinMeta data: As the deadline for federal tax filing in 2025 approaches, American crypto investors need to submit their tax returns by October 15, 2026. IRS indicates that taxpayers who request an extension do get additional time to file their taxes, but unpaid taxes begin to accrue interest and late fees from the original deadline. During the first tax-filing season of 2025, many custodian brokers already reported sales of digital assets on the 1099- da form. The new form provides more transaction data, but most reports do not include the cost basis for investors. IRS warns that taxpayers must calculate the original purchase cost of their assets themselves to determine gains or losses. The 2025 1040 form requires each taxpayer to answer questions regarding digital assets, and IRS explains that taxpayers who have received digital assets need to report the related income. IRS also points out that unpaid taxes may be subject to late fees, which are typically 5% of the unpaid amount.