I received a CP2000 Notice from the IRS because I did not report gambling winnings. I need to report those winnings, and also deduct my gambling losses for 2020.

[k.arquines]

I do not have the W2-G forms from those winnings. The sportsbook (a legally operating State Lottery) has sent me a record of my monthly Win/Loss for tax year 2020. I need to deduct my losses against my unreported gambling winnings.

[DoninGA]

You will have to amend your 2020 federal tax return to report the gambling winnings and losses.

See this TurboTax support FAQ for amending a 2020 tax return originally completed and filed using TurboTax - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-2020-return/L3XdA1Pw8_U...

Gambling winnings are reported on a tax return as ordinary income.  Gambling losses are reported as a Miscellaneous Itemized Deduction on Schedule A.  You DO NOT subtract your losses from your winnings when reporting your winnings on a tax return.

If the total of all itemized deductions on Schedule A are less than the Standard Deduction for your filing status then Schedule A will not be used for deductions.

Standard deductions for 2020

• Single - $12,400 add $1,650 if age 65 or older
• Married Filing Separately - $12,400 add $1,300 if age 65 or older
• Married Filing Jointly - $24,800 add $1,300 for each spouse age 65 or older
• Head of Household - $18,650 add $1,650 if age 65 or older

To enter, edit or delete Gambling Winnings and Losses -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to Less Common Income
• On Gambling Winnings, click the start or update button

[NCperson]

@k.arquines - I assume you have already filed 2020 and need to amend...

suggest looking at your transcript at IRS.GOV because I imagine it was reported by the Sports Book so you want to make sure what you report equals or exceeds what they reported on Form 1099-G.   These will get added to income on the amendement form.

with respect to losses, they are reported as an itemized deduction and cannot exceed the winnings; if you take the standard deduction, none of the losses are deductible.