The first important principle to remember when it comes to taxes is this: Taxable events are taxable whether or not anything is reported to the IRS by someone else. You are legally required to report and pay tax on your taxable activities, even if the IRS doesn’t yet know about them. Taxes are sort of on the “honor system,” until you get audited.
So let’s look at each of your listed activities to see which ones are taxable. Please note that your activity #3 is really two activities, and I have split them apart below.
- Purchase $1000 USDT on Binance
The initial purchase of a cryptocurrency is not taxable.
- Transfer to a crypto exchange outside the U.S., or transfer to a wallet address and use decentralized exchange.
This is not taxable, either. However, remember that while moving it outside the U.S. may avoid your transactions being reported to the IRS, it will not relieve you of your own reporting and tax obligations.
- (a) Buy bitcoin [for $1000 USDT].
Tax wise, when you buy one crypto with another, this is treated as if you had sold the first crypto and bought the second crypto with cash. However, because USDT is tethered to USD, selling the USDT results in no taxable gain. So far, still no taxable events.
- (b) Sell [bitcoin] for $2000 [USDT].
Here is where it happens. When you buy USDT with Bitcoin, it is treated as if you had sold the Bitcoin for cash, then purchased USDT. This is taxable. You would need to report and pay tax on a $1000 capital gain.
- Transfer $2000 USDT to my wife or father's Coinbase account, cashout.
In the U.S., gifts under $15000 per year are not taxable, and gifts to your wife are never taxable. The recipient of your gift would have a cost basis on his or her crypto holding of $2000, which is what the cost basis was of your USDT holding. No tax for them when they cash out.
Note: If you had given your wife or father your Bitcoin holding instead of first converting to USDT, you would avoid the taxable event in step 3(b). However, in that case, your recipient’s cost basis in the crypto would be only $1000 instead of $2000, and when they cash out, they would have to pay the capital gains tax that you avoided.