Microsoft has started phasing out Reserved Instance purchases for a number of older Azure VM series — Dv2, Dv3, Ev3, and other legacy generations — with new purchases and renewals cut off as of July 1, 2026, according to Microsoft's own transition guidance. If you're not actively tracking your Azure reservations, this is the kind of change that slips past entirely, because nothing about the affected virtual machines actually changes on the day it happens.
That's the part worth flagging to whoever owns your cloud bill. The VM keeps running exactly as it did. There's no restart, no downtime, no alert banner in the portal demanding attention. What happens instead is that the moment your existing reservation term expires, Azure quietly starts charging the full pay-as-you-go rate — and depending on the VM family, that can mean paying 40 to 70% more per month than the day before, with nothing in the environment itself indicating why.
Microsoft's guidance gives two real paths forward: migrate the affected workloads to a current-generation VM series (v5 or v6), which usually comes with better price-performance anyway, or shift that spend to an Azure Savings Plan for Compute, which trades some of a reservation's deeper discount for flexibility across VM families and regions. Existing reservations already purchased continue to honor their original term — this only affects new purchases and renewals going forward.
The practical step takes about five minutes: open the Reservations blade in the Azure portal, filter by VM series, and check which of your active reservations sit on one of the affected legacy families with a renewal date anywhere in the second half of 2026. Better to catch it there than in next month's invoice.