Founder and editor
Md Sayful Islam is a web developer from Bangladesh who has built and run websites since 2017. He also runs Themeve, a store that sells WordPress themes and plugins, some of them by subscription. He researches every Billing Model guide from primary sources such as accounting standards, card-network rules and platform documentation, and links to them in each article.
ACH processing fees are what a US business pays to send or collect a bank-to-bank payment. They are usually flat or capped, which is why ACH wins on large invoices.
10 min read
A net 30 invoice must be paid in full within 30 days of the invoice date. Here is how to count the due date, word the invoice and price a 2/10 discount.
9 min read
A recurring invoice is one template that produces a new numbered bill on a schedule. Here is what to set, a filled-in example and the mistakes to avoid.
9 min read
The six main SaaS pricing models side by side, with one customer's bill worked out under each and what research says about flat versus metered bills.
10 min read
The ten SaaS metrics a subscription business tracks, from MRR to CAC payback, with a formula for each, one worked month and the reason no two companies define them alike.
10 min read
Payment processing fees are split between the card-issuing bank, the card network and your processor. Here is what each part is, with a $100 sale worked through.
11 min read
Invoice payment terms say when a customer must pay and what changes if they pay early or late. Here is what each common term means and how to pick one.
10 min read
Subscription billing is a repeating cycle of charge, collect and renew. Here is each stage in order, with a proration example and what regulators expect.
10 min read
Usage-based pricing charges each customer for what they consumed in the period. Here is how usage is metered, rated and billed, with a worked bill.
10 min read
