billing module

Question

I'm launching a small service and plan to charge monthly (eg- will be advertised as $10 monthly). I'm working on the billing module right now but was wondering about a small bit:

I plan to bill customers when they first register and then at regular intervals thereafter. Getting to my question- Some months have less than 30 days. Does monthly billing imply exactly a 30 day interval or would anything between 28-30 days be considered a monthly interval?

I was planning on doing 30 because it seems that's what customers would expect, but I'm also curious if some companies charge at a fixed interval other than 30 days.

Answer 1

Billing monthly is assumed to be 12 times per year, not once every thirty days.

Preferably, billing should be on the anniversary of the original billing date of the month. If the current month has fewer days than the original billing DOM, bill on the last day of the current month, but on the next month, bill again on the anniversary day.