In general, distributions from a traditional IRA are taxable in the year you receive them. You will receive Form 1099-R, Distributions From Pensions, Annuities, Retirement or Profit-Sharing Plans, IRAs, Insurance Contracts, etc., which reports your total distribution amount, taxable amount, and any tax withholding taken. However, the IRS Form 1099-R you receive will not specify that this was an RMD distribution.
Consult a qualified tax professional to understand your individual tax liability.