You shouldn't get a cash discount - cash costs the merchant MORE than credit card fees. You have to count all the costs of cash that credit cards don't have: counting, and recounting the cash and change. Then the manager counts and recounts everything in the back room at the end of the shift. Then the manager counts everything twice again to write up the deposit forms. Plus you need a cash register with the extra cash drawer that acts like a safe. Plus other security systems just to prevent robbery (this can get elaborate in areas where robbery is common). Those all add up.

▲ matheusmoreira 15 hours ago | parent [-]

> You shouldn't get a cash discount

Maybe, but "should" has nothing to do with it. Either I get one or I use my credit card.

> cash costs the merchant MORE than credit card fees

That's not my problem.

▲ bluGill 14 hours ago | parent | next [-]

None of this is your problem: you are not a merchant. What is wrong is the analysis of various people who think cash is cheaper and thus get mad at not getting a cash discount. It is also wrong that a number of merchants are bad at accounting: they think that cash is cheaper by enough to be worth a discount - but this is not your problem either.

▲ greyw 14 hours ago | parent | prev [-]

Just pay with a credit card, it's the optimal way by far (float, flexibility, rewards). No need to overthink it.

▲ matheusmoreira 13 hours ago | parent [-]

It's worth to think about it a bit, especially in larger purchases. Significant discounts on the order of 5% to 10% can easily beat all credit card benefits, and not taking advantage of it leaves lots of money on the table.

I have a little lookup table for this. Interest free installments mapped to cash discount necessary to beat the credit card. I just look it up.

   1x -> ~1.9%
   2x -> ~2.3%
   3x -> ~2.8%
   4x -> ~3.2%
   6x -> ~4.0%
   8x -> ~4.9%
  10x -> ~5.7%
  12x -> ~6.6%
  18x -> ~9%
  24x -> ~11-12%

These numbers are actually conservative. There's a lot of credit card benefits that weren't priced in. I add a couple percent to the required discount numbers and round it up to compensate.

   1x ->  4%
   2x ->  5%
   3x ->  5%
   4x ->  6%
   6x ->  7%
   8x ->  7%
  10x ->  8%
  12x ->  9%
  18x -> 12%
  24x -> 14%

	▲	bluGill 13 hours ago \| parent [-]
		Mathematically you are right. However those interest free payments are generally setup in such a way as to make it highly likely you won't pay it off by the end of the interest free period. The bills they send contain the minimum payment - designed to get you past that time. I don't trust my ability to get the fine print right - it only takes messing this up once to destroy all the gains from several times getting it right. So I use the credit card anyway and pay it off every month - that payoff is the one number I can get right every month.