Key Takeaways

• The decision is a financing one. On a $40,000 monthly account, Net 60 postpaid terms lock $120,000 of working capital that prepaid never touches.

• Postpaid stretches further than most teams model. AWS Marketplace private offers support terms up to Net 120, putting cash 150 days behind the start of service.

• Prepaid caps your loss at the unfunded balance, because a customer who disappears has already paid for what they used.

• Prepaid cash is a liability until you deliver, so it lands in deferred revenue rather than the income statement.

• Most products run both models on one meter: self-serve prepaid, contracted postpaid.

What's the difference between prepaid and postpaid billing?

Prepaid collects first and meters against the balance, postpaid meters first and invoices against the record. Everything else follows from that ordering: who carries the risk, and who funds the gap.

The charge timing underneath each column belongs to the sibling pages: billing in advance covers charging at the start of a period, billing in arrears covers invoicing after it closes. Prepaid and postpaid sit a level up, describing the relationship rather than the line item.

Prepaid is a balance, not a schedule. Advance billing charges a known amount for a period ahead, while prepaid takes money for consumption whose shape stays open. That's why prepaid credits behave nothing like an annual fee collected in January.

Which billing model should you pick?

Pick prepaid when you can't underwrite the customer, and postpaid when the customer won't accept anything else. Enterprise procurement won't wire money against an unknown quantity, and an unverified signup isn't worth 60 days of credit.

The working capital difference on a $40,000 per month account:

Three months of revenue sits permanently outstanding in that column, and it grows with you. Stretch to Net 120, which AWS documents as a supported private offer term, and the same account ties up $200,000.

What I'd weigh before committing:

• Gross margin. A product paying inference costs on day 3 and collecting on day 91 lends money at its own cost of capital.

• Write-off rate by segment. If self-serve accounts write off above a couple of percent, prepaid pays for itself.

• Deal size. Below roughly $1,000 a month, collections cost more than the account earns.

What breaks when you switch between them?

Revenue recognition breaks first, because the two models put cash and revenue in different periods. A month spent moving customers onto prepaid shows cash climbing while recognized revenue stays flat, and finance reads that as an error unless you warn them.

The failures that recur on a migration:

• The double-bill month. Switching a customer mid-cycle invoices the closing arrears period and charges the new balance in the same week. Bill one, defer the other.

• Stranded balances. Customers leaving prepaid carry an unspent balance you now owe them, and the refund policy rarely exists before the first request arrives.

• Enforcement gaps. Postpaid accounts bound exposure with spending caps. Drop the cap assuming the balance enforces it, grant one courtesy overdraft, and nothing stops the meter.

• Unbilled AR vanishing. Prepaid conversions retire the unbilled AR the forecast was built on, which reads as a revenue drop in any report keyed to invoices.

Related terms

Timing, balances, and payment terms are what this comparison turns on.

• Billing in advance covers the mechanics of charging before a period starts.

• Billing in arrears covers invoicing once the period closes and usage settles.

• Prepaid credits is the instrument most prepaid models actually use.

• Spending cap bounds exposure on the postpaid side.

• Net 30 payment terms sets how far postpaid cash sits behind delivery.

• Credit rollover decides what happens to an unspent prepaid balance.

FAQ

Is postpaid billing the same as billing in arrears?

They describe the same arrangement from different angles. Postpaid is the commercial relationship, where the customer consumes on credit and pays later. Billing in arrears is the invoicing mechanic, where the invoice issues once the quantity is known.

Is prepaid money revenue when the customer pays?

No. Prepaid collections are a liability until you deliver. A customer who funds $10,000 in March and consumes $3,000 of it recognizes $3,000 of revenue that month, with $7,000 in deferred revenue.

Can one product run prepaid and postpaid at the same time?

Running both at once is the common end state, not an edge case. The meter is identical across both, and the difference is whether consumption draws down a funded balance or accrues against an invoice.

Which model has fewer payment failures?

Prepaid fails earlier and cheaper. A declined top-up stops service before the customer consumes anything you can't recover, while a failed postpaid payment lands after a month of delivered service. Prepaid trades collection risk for signup friction.