Since 1 July 2026 Microsoft no longer sells reservations for the first-generation B-series. For finance and FinOps that raises different questions than for IT: how the invoice will change, which commitments still make sense, and by when decisions are due.
Do existing reservations keep running?
Yes, until the end of their term. Azure does not renew them afterwards, even with auto-renew switched on. From that day the VM is billed at pay-as-you-go rates, with nothing changing in the environment.
How much does cost rise afterwards?
On its legacy pricing page Microsoft shows around 54 percent savings for the Bs series with a three-year commitment and around 32 percent with one year. Without a commitment the same VM costs roughly 2.2 or 1.5 times as much.
In Cost analysis, the amortised view grouped by pricing model shows which usage already runs without a discount.
Why can I not see any reservations although I own the subscription?
Reservations are managed at billing scope. Rights on a subscription are not enough to see them, not even as owner. You need read access at billing or reservation scope. Without it the list appears empty, which says nothing about what actually exists.
Can a Bv1 reservation be exchanged?
Yes, for example into a reservation for Bsv2 or Basv2. Until 1 February 2027 this is freely possible. From that day Microsoft stops exchanges for services covered by savings plans, and each eligible reservation bought before the deadline keeps one final exchange.
An exchange only makes sense once target size and region are settled. If the final exchange after the deadline goes to the wrong size, there is no second one.
Is a savings plan the better choice?
For environments that will change over the coming months, usually yes. A savings plan commits an hourly amount instead of a VM type, applies across families and regions, and still covers Bv1.
There are two traps when sizing it. Reservations are applied before the savings plan, so the amount must fit what remains. And it should reflect consumption after modernisation, not today’s invoice. Unused hours are lost.
When is no commitment the right answer?
For VMs that will be replaced or switched off within a few months. Microsoft’s own transition guide says this should be a conscious decision, not an accidental outcome. In practice that means every uncommitted VM gets an end date and an owner.
Are there exceptions for large estates?
No. Microsoft plans neither exceptions nor extensions and points to the account team, to modernisation and to alternative commitment models.
In which order should decisions be made?
- Define the target state per VM: replace, consolidate or decommission.
- Exchange reservations for stable load in the target state while free exchange is still possible.
- Size the savings plan on the remaining load after migration.
- Give the uncommitted remainder an end date.
Where the analysis comes in
Most of these answers depend on data that rarely sits in one place: the reservation inventory, expiry dates and the planned target state per VM. The cost and migration analysis brings them together and derives the exchanges, the savings plan amount and the deliberately uncommitted remainder. Three to five weeks, fixed fee, implementation stays with your team.
Sources (as of 10 October 2026)
- Azure Update 560948: end of Reserved VM Instances for selected series from 1 July 2026
- Microsoft Learn: Transition guide for retired Azure Reserved VM Instances
- Azure Update 568514: reservation exchanges for services covered by savings plans end on 1 February 2027
- Microsoft Learn: VM size series retirements, capacity growth restrictions, and modernization guidance
- Microsoft: Legacy Generation Virtual Machines Pricing (Bs series)