Are you talking about a no fee, full purchase APR BT? Capital One would still get 7-10 days of interest income off of you so they wouldn't really be out anything. Can't see them getting upset about that.
It's interest income they wouldn't have otherwise gotten, I don't see them taking issue with it at all.
Shouldn't be an issue for any of the major card companies, honestly. They're getting paid regardless, either via a tiny bit of interest or the transfer fee. I've not paid down a balance transfer as quickly as a week and a half, but I've paid off 12-month and 15-month transfers in as little as 2 months.
Didn't hear a peep.
OK, here's one for which I have an answer that may actually be useful!
First, others who have assumed that interest would be charged immediately are probably wrong. Unless things have changed just recently, CapOne cards will actually do a BT as a pseudo-purchase -- they don't incur interest until the next statement cuts and the balance hasn't been paid off by the due date. Of course, if there's a revolving balance, this doesn't apply.
I took advantage of this odd feature a couple years ago. I had a 0% BT expiring on a Barclay card and a BT offer for just 1% BT fee on the same card. So I BTed a few thousand to CapOne, then as soon as it arrived there, I BTed it back to Barclay for another year at 0%. I had multiple BT balances on the Barclay card and, as each came due, I paid it off (pmts were applied to earliest-expiring offer, thankfully) and then sent it back. I did this probably half a dozen times, for a total amount of maybe $28k. It worked every time. Never paid CapOne anything. Life was beautiful.
Until it all went bad. CapOne decided that they no longer wanted to maintain a business relationship with me. They shut down both cards I had (and I'm pretty sure I never used the smaller one for these BTs) as well as a CapOne 360 account I had tried to open for a bonus.
Now, my Walmart card just transitioned from Synchrony to CapOne. I had a zero balance and essentially never used that 10K of credit line, but as soon as it showed up at CapOne it went pretty much immediately to "restricted" status and I got a credit-monitoring alert that it had closed (in addition the Synch acct, so 2 notifications). It still shows as open/current/never late, etc. but I believe it really is gone. That with a true FICO of 750 and up on all 3, perfect payment history, no derogatories, etc. So, I'm clearly on CapOne's black list.
So, if you do it, do it just once. Or don't do it.
Interesting. I wasn't aware that they actually give you a grace period before charging interest. I suppose that would indeed change things since they wouldn't be getting anything from the BT.
Yeah, that feature was quite useful to me at the time. I don't recall how I became aware of it; probably from this very site.
Notably during this whole period, even with repeated runs to within a few hundred dollars of my $32.9K limit on the Barclay card - BTs, BTs paid off, new BTs a week later, *many* times, mixed with actual purchases (yep, they gave the grace period on purchases despite their being mingled with BTs) - Barclay never made a peep. I still have the card (former SallieMae), although the super-cheap BT offers have gone away for now. Luckily, I don't need them now. 8-)