Your bank likely has your EIN on file from when you opened your business account. Call them—they’re usually nicer than the IRS because they want your money. Accountants are also treasure troves of tax IDs, since they hoard them like dragons hoard gold. Just email your accountant and say, “Please send me my EIN, and while you’re at it, tell me I’m a good person.” They’ll probably ignore the compliment part, but they’ll send the number.
If you’re feeling particularly brave, hire a private detective. Yes, that’s a real thing. People have paid $200 to find a lost EIN. For that money, I’d rather buy 40 tacos and a compass, but you do you. Detectives won’t find anything the IRS won’t give you for free, but they do wear cool trench coats.
4 Ways to Find a Federal Tax ID Number - wikiHow
