One-time prorated charge
—
How it is calculated
How it appears on the billing report
Microsoft reverses the existing seats at the prorated rate, then re-charges the full new quantity. Two lines, one net effect — this is why the report looks alarming at first glance.
| Charge line | Qty | Unit | Amount |
|---|
What happens next
| Period | Covers | Charge |
|---|
How this matches Microsoft's billing
The engine applies Microsoft's NCE proration rule:
prorated unit price = unit price × (days remaining ÷ days in billing period)
Both endpoints count as charged days: the order date is billed, and so is the last day of the period.
Which window gets prorated
| Term | Billing plan | Added seats are prorated… |
|---|---|---|
| P1M | Monthly | order date → end of the term |
| P1Y | Monthly | order date → end of the current month cycle, then full price each month to term end |
| P1Y | Annual | order date → subscription end date, charged once |
| P3Y | Monthly | order date → end of the current month cycle, then full price monthly to term end |
| P3Y | Annual | order date → end of the current annual cycle, then full price yearly to term end |
| P3Y | Triennial | order date → subscription end date, charged once |
Billing cycles are anchored to the subscription's start day-of-month. A subscription starting on the 11th bills the 11th to the 10th, not calendar months.
Which price to enter
The term commitment and the billing plan together pick the price list row, so the price field's label follows both: a one-year commitment billed monthly wants the per-month price, the same commitment billed annually wants the per-year price.
Never convert between them. Visio Plan 2 is one SKU with three list prices:
| Term | Billing plan | List price |
|---|---|---|
| P1M | Monthly | $16.00 per seat / month |
| P1Y | Monthly | $14.00 per seat / month |
| P1Y | Annual | $160.00 per seat / year |
A one-year commitment billed monthly is not a P1M price — P1M is a shorter commitment on a dearer SKU. Nor is the annual price twelve monthly ones: $14.00 × 12 is $168.00, but the annual figure is $160.00. Scaling or substituting produces a price that appears on no price list.
An estimate for sales conversations. The Microsoft billing report remains the source of truth.