Hi Sandra,
When paying taxes with a credit card, it's most efficient to use one that you're trying to meet a minimum spend on as you'll get the best return. You can even split the payment between two cards, so you could likely get two bonuses with the right pairing. If going that route, a great card to open and use would be the Freedom Unlimited (
https://tinyurl.com/yx9nohkj) which is currently offering a 20,000 UR welcome bonus plus 1.5 UR/$ on regular spend and an additional good bonus on grocery for the first year.
You could also look at applying for the Chase Ink Preferred and getting 100k points by overpaying your balance due to meet the $15k spend (if you can float it until the IRS sends you a check for the difference), or a combination of both cards.
In the future, you could also pay "estimated" payments as well as overpay the amount owed to double-down on using cards for taxes. For example, if you know you're going to owe $7k you could do an estimated payment of $3k in December on a new card, and then when taxes are due in April pay $4k on another card (or $10k or $50k or however much you can/want) and then get the overpayment refunded.
Again, I would focus on Chase cards since you're under 5/24 and also because their currencies are the most flexible in case you don't plan to travel anytime soon as you say.
Hope that helps!
