How does premium credit work?

When you have premium credit, that balance is used toward your next premium payment. Except you always pay at least $1, for accounting (and confirming-your-payment-method-still-works) reasons. It's not a nickel-and-diming thing — that dollar is carried over and applied as credit on your next payment so it's all exquisitely fair and equivalent to reducing what you pay by the full amount of credit you got, just not in the same month.

Can I use premium credit toward upgrading my subscription?

Yep! Premium credit is applied to anything to do with premium plans. It all happens automatically — there's no choice to not apply it.

Can you apply premium credit towards my derailments?

Noooo, that would be sting dilution. Derailments need to hurt as much and as immediately as possible! In particular, if you could rationalize in the back of your mind, "well, I could go for this run but it's raining and I have this credit balance to use up anyway..." then that's making Beeminder less effective at motivating you.

(Also we didn't implement this feature that way, so it's currently technically impossible as well as philosophically. And perhaps in the future we'll change our mind on this. It's not totally outrageous, philosophically speaking, to apply credit to derailments. It just means treating that credit balance as absolutely the same as money, which maybe is fine! But, again, is not the status quo.)

Can you give an example of how premium credit affects payments?

Imagine you point out a grievous error in these help docs and we give you $10 of premium credit as a thank-you. Imagine as well that you're paying $8 monthly for the Infinibee premium plan. In that situation, next time your premium payment comes up you'll pay $1 of the $8 you owe, with the other $7 coming off your premium credit balance. That leaves you with $3 of the original $10 left as credit. That $3 will be used against your next payment. Next month, you'll pay $5 and your $3 of premium credit will be all used up, leaving a balance of $0. Every month thereafter you'll pay the normal $8.

If that was confusing, it's almost the same as if you used $8 of your $10 credit the first month, paying nothing, and the remaining $2 of your credit the next month, paying $6 instead of $8. Instead it's shifted slightly but you're still paying $10 less than you would've thanks to that $10 of credit.

Why not do it the unconfusing way again?

A few reasons!

1. We like complicated things. No wait, this is not a real reason.
2. It's valuable to have the audit trail by logging a real transaction for every premium payment.
3. It ensures that your payment method still works and Beeminder is still a credible threat.
4. Our payment processor doesn't let us charge less than a dollar so if you happen to owe less than a dollar, this is an elegant way to deal with that. Pay $1, get your change as credit to be applied next time.
5. Technical reasons like fewer special cases in our code (like the $0 case in reason #4). We're not sure how real of a reason that is. We could swap in this one: It's how we implemented it and we've already spent way too long on making this all work Just So and don't want to mess with it again.

Do you pay interest on my premium credit balance?

Who do you think we are? Of course we do. Currently 2%/year, compounded continuously.

Is there such a thing as negative premium credit?

Yup! In case for some reason you owe us money, it's just as easy for us to give you negative credit and then all the mathematically correct things happen (you'll pay that much more next time you're charged for a premium payment).

What about imaginary amounts of credit?

I mean, probably that would work? We're drawing the line at quaternions though.

Keywords: premium credit, discounts, overengineering, math nerds, compound interest