So, after snagging a new AMEX card and needing to spend $10k in the next 4 months, I've sketched out how I will do this. I'm going to owe the IRS some money ... not tons, but it would help massively with this "burden". This spend would be easy for us, but we're also trying to spend large on the Discover card for a targeted bonus ... this requires 3k per month through August. I paid my city's estimated tax for 2012 in December with the BB card. I was a bit worried, but I supplied my city account # to BB and sent a check. Called a week later and the tax office confirmed receipt! Ditto with my car loan payment, which I do now regularly. And my Home Equity line of credit payment. All with trusting BB to relay the account number I've recorded for each, and it seems to be working. So, now I'm wondering about US Federal Income Tax. Typically I send a check in WITH my return. However, typically, I send in my city estimated tax with a voucher, but I didn't this time, and it worked. If I send the IRS a BB check with my account number on it, would this also just go on my records, I wonder. Do I send this before or after the tax return itself? Can I send a check NOW and file the taxes in a week or so (making up the difference, if any, then)? RELATED QUESTIONS. First, wouldn't it be nice if we could upload a scan, pdf or picture to send with a BB check? To represent the "slip" you usually mail in with the check. What if I make a check out to a company ... in my real case, a small home painting firm, but have it sent to MY home address. I don't want to pay them until they are done with the job, and I don't want to tell them, when they ARE done, that they have to wait 2-3-4 days or more to get paid. Yeah, that would go over well. "It'll be in the mail!" Anything wrong with having BB send a check to my address, made out to someone else? This would also solve the IRS problem. I wonder what the BlueBird check looks like. Perhaps I'll send one to my wife and see! Does anyone know, in the meantime?? Sorry for the long post, but thanks for listening!