The signup bonuses there's usually a good up to date list here:
Normally you'd want to start a bit earlier, but if you have a spouse they too can do signups, making it easier to get a bunch in a relatively short time if you have the spend available which you do via the tax bill.
Also don't be put off by half of these being "business" cards... If you say you have a business- you do. Sole proprietorship using your SSN and there ya go.
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A few examples with larger spend requirements since you have a 6 figure bill I'd imagine? Note- in all cases you get additional points for the spend itself, though mainly this will offset the 1.x% fee for paying taxes with a card, leaving the main bonus as net profit.
Chase Ink Preferred gets you 100k chase points for 15k spend (so that's $1000 if taken as cash, if used for travel the value will range from $1250 to as potentially over $5000)... that'll knock out 30k spend alone if you get one for you and one for spouse.
Amex Biz Plat is 150,000 Amex points for 15k spend per card ($1500 taken as cash, considerably more used for travel)
Capital One Business Spark Cash Plus - $3000 cash for 50k spend
Amex personal gold 90k pts on 4k spend (90k will be $900 cash, so over a 20% return on spend- again considerably higher value if used for travel).
Normally when you have more time you can also swap referral links between you and your partner to increase the bonuses too though in your case you likely don't have time before 4/15 to wait for one of you to get cards and then refer the other to them.
The 0% interest is a different/alternative strategy thing- there's SOME overlap in that those cards do usually have a signup bonus, though it's usually a smaller one with smaller spend.... we mainly do it for the signup bonuses rather than the extra time- and you can of course sign up for more than one card, we've got more than enough to cover a 6 figure tax bill for example and we're knocking several more large signups out with this past years tax bill.
We also mainly use the bonuses for premium travel, so for us 100k pts instead of $1000 cash will go to buying a roundtrip business class plane ticket that'd normally cost $5000 or something...pretty good return on just paying your taxes.