Modernization & Cloud

Azure vs AWS Cloud Migration: Which to Pick, and Why

8 min read

Pick Azure if your shop already runs on Microsoft, Windows Server, SQL Server, and .NET, and you hold an Enterprise Agreement. Pick AWS if you want the widest service catalog, the deepest bench of engineers who already know it, and the largest market share to hire against. That’s the whole decision in two sentences. AWS still leads global cloud infrastructure at 28% of spend, versus Microsoft’s 21% and Google Cloud’s 14% in Q1 2026, but market share isn’t your tiebreaker. Your existing estate is.

We’re gmware, a custom software development firm in Austin, TX with engineering centers in Bangalore and Mohali, India, and we run cloud migrations for mid-market companies onto both platforms. This post is the decision guide we walk buyers through before they commit: the four axes that actually move the choice, a matrix for which shop picks which, the migration tooling on each side, and the honest case for picking neither yet.

Your existing Microsoft estate usually decides this

Usually, yes. If your servers run Windows, your databases run SQL Server, and your apps are .NET, Azure has a pricing lever AWS can’t match: Azure Hybrid Benefit lets you apply licenses you already own to Azure VMs. Microsoft says that combined with reserved instances, you can save up to 85% over pay-as-you-go rates on Windows Server and SQL Server workloads. Take those claims with a grain of salt (they’re Microsoft’s own, and the headline number stacks every discount at once), but the mechanism is real and it’s specific to Azure.

The same logic runs the other way. If your team already lives in AWS consoles, has IAM policies tuned, and knows where the bodies are buried in your VPC, moving to Azure means re-learning all of it. The cheapest migration is often the one that lands where your people already have muscle memory. Skills you already have are a cost line, even when nobody puts them on the invoice.

Here’s an opinion we’ll defend: for a Microsoft-first shop with an Enterprise Agreement, the AWS-vs-Azure debate is mostly over before it starts. The EA discount plus Hybrid Benefit plus existing AD integration tilts the math hard enough that “we should evaluate AWS too” is often a way to spend three weeks confirming what the license agreement already told you.

AWS breadth only matters if you’ll use it

Sometimes. AWS has more services and more maturity in most of them, and a bigger community means more Stack Overflow answers, more Terraform modules, and more engineers who’ve already shipped on it. If you’re building something unusual (heavy data pipelines, niche managed databases, bleeding-edge ML tooling) AWS often has a first-party service where Azure has a partial answer or a partner.

But breadth is only an advantage if you’ll use it. Most mid-market migrations are boring in the good way: some VMs, a couple of managed databases, a Kubernetes cluster, object storage, a load balancer. Both platforms do all of that well. Paying an “AWS is more complete” premium in re-training and re-tooling to reach services you’ll never turn on is a bad trade. Count the services you’ll actually run in year one, not the catalog.

Egress is the hidden cost, but it rarely flips the answer

Egress is the fee for moving data out of the cloud to the internet, and it’s the line item that surprises finance six months in. On this axis, AWS and Azure are close enough that egress rarely picks the winner, but you should know the shape. After a 100 GB monthly free allowance, AWS charges $0.09 per GB for the first 10 TB of internet egress each month in US regions. Azure charges $0.087 per GB for the same tier in its US and Europe zone. Effectively a wash.

Where egress actually bites is architecture, not provider. If you’re serving media, running cross-region replication, or pulling large datasets back on-prem, egress can turn into a five-figure monthly surprise on either cloud. The fix isn’t picking the fractionally cheaper provider. It’s a CDN in front of heavy traffic, keeping chatty services in the same region, and modeling the data-out volume before you sign. We cover the broader bill in our cloud migration cost guide for smaller teams, because provider choice is a small slice of what a migration actually costs.

AWS MAP vs Azure Migrate: which migration path is smoother?

Both vendors will help you move, and both attach money and tooling to doing it their way. They just package it differently.

AWS runs the Migration Acceleration Program (MAP): a three-phase framework (assess, mobilize, migrate) with partner expertise and funding incentives attached. AWS cites average infrastructure cost reductions of 31% for MAP migrations, which is a vendor number but a useful directional one. MAP is strongest when you’re moving a large, mixed estate and want AWS credits and a certified partner to de-risk it.

Azure leads with Azure Migrate, a free unified hub that discovers your on-prem inventory, assesses Azure readiness and cost, builds a business case, and executes the move for servers, databases, web apps, and virtual desktops. It’s tightly wired to the Microsoft stack, so if you’re lifting VMware or Hyper-V VMs and SQL Server databases, the assessment-to-migration path is unusually clean.

The honest read: Azure Migrate is a more integrated first-party tool for a Microsoft-heavy source environment. MAP is more of a program (money, partners, methodology) than a single tool, and it shines on large heterogeneous estates. Neither one makes a bad target platform good. If the destination is wrong for your workload, better tooling just gets you to the wrong place faster.

Which shop should pick which? A decision matrix

Match your situation to the row. Most companies see themselves in the first two.

Your situationPickWhy
Windows / SQL Server / .NET estate, Enterprise Agreement in placeAzureHybrid Benefit + EA discount + AD integration you already run
Team already deep in AWS, tuned IAM and VPCsAWSRe-training onto Azure costs more than any pricing gap saves
Building something niche (heavy data, unusual managed services)AWSDeeper first-party catalog and larger engineering hiring pool
Mostly VMs, databases, Kubernetes, object storageEitherBoth handle the boring 80% equally well; let skills decide
Heavy Microsoft licensing plus a small ops teamAzureFewer moving parts to learn; Azure Migrate does the assessment
No cloud skills in-house, hiring against the marketAWSLargest talent pool and community to hire and troubleshoot against

When the answer is neither, or not yet

Here’s the verdict the vendors won’t give you: sometimes the right move is to not migrate, or to not pick one.

Stay multi-cloud on purpose when you have real workloads that each land better on a different platform, or when a single-vendor commitment would hand one provider too much pricing power at renewal. That’s a legitimate strategy, but it isn’t free. Running two clouds means two skill sets, two billing models, and two security postures to keep straight. Most mid-market teams underestimate that tax. If you’re weighing it, our take on running more than one cloud without doubling the headache lays out where it pays off and where it just doubles the work.

And sometimes the honest answer is don’t migrate yet. If your app is a tangle nobody wants to touch, lifting it to a new cloud as-is just moves the mess and adds a monthly bill. The right first project might be modernizing the workload where it sits, or fixing the data layer, before any provider enters the conversation. Pointing a migration at software you don’t understand is how a clean lift-and-shift turns into a six-month archaeology dig.

One more honest answer: don’t decide alone. The choice compounds. Egress terms, license portability, and the skills you hire against all get harder to reverse a year in, which is exactly why we scope it before anyone touches a console.

How gmware runs the AWS-vs-Azure call

We start with your estate, not our preference. Our cloud migration practice inventories what you run today (OS, databases, licensing, egress volume, who on your team knows what) and reads the answer off that, because in most cases the estate has already voted. We’re comfortable landing you on either platform, and we’ll tell you when the right answer is neither yet.

When the call is close, we model it: a real cost projection with your egress numbers, your license position, and your team’s ramp time priced in, not a generic calculator screenshot. Our cloud consulting team runs delivery from Austin with engineering in Bangalore and Mohali, which keeps senior architects on US hours without US-only burn rates.

Tell us what you’re running now and where you’re thinking of moving it, and we’ll give you a straight AWS-or-Azure recommendation, with the cost model and migration plan behind it, within 48 hours.

  • cloud migration
  • azure vs aws
  • cloud strategy
FAQ

Common questions, answered

Is Azure or AWS cheaper for a cloud migration?
It depends on what you run. If you own Windows Server and SQL Server licenses, Azure Hybrid Benefit lets you reuse them on Azure VMs, which AWS can't match, and Microsoft claims up to 85% off pay-as-you-go when stacked with reserved instances. For non-Microsoft workloads the two are close, and egress is nearly identical at roughly $0.09 versus $0.087 per GB.
Should a Microsoft shop always choose Azure?
Usually, but not automatically. If your servers run Windows, your databases run SQL Server, and you hold an Enterprise Agreement, the EA discount plus Hybrid Benefit plus existing Active Directory integration tilts the math hard toward Azure. The exception is a team already deep in AWS with tuned IAM and VPCs, where re-training cost can outweigh the license savings.
What is the difference between AWS MAP and Azure Migrate?
AWS Migration Acceleration Program (MAP) is a funded three-phase program (assess, mobilize, migrate) with partner expertise and credits, strongest for large mixed estates. Azure Migrate is a free unified tool that discovers, assesses, and migrates servers, databases, web apps, and desktops, and is tightly wired to Microsoft workloads like SQL Server and VMware. MAP is a program; Azure Migrate is a tool.
Does cloud egress cost differ enough to pick a provider?
Rarely. After 100 GB free each month, AWS charges $0.09 per GB and Azure $0.087 per GB for the first 10 TB of US internet egress, a rounding-error gap. What drives your egress bill is architecture, not provider: media serving, cross-region replication, and pulling data back on-prem. Model the data-out volume and use a CDN before you sign anything.
When should you stay multi-cloud instead of picking one?
Stay multi-cloud when specific workloads genuinely run better on different platforms, or when a single-vendor commitment would hand one provider too much pricing power at renewal. It isn't free: two clouds mean two skill sets, two billing models, and two security postures. Most mid-market teams underestimate that overhead, so choose it deliberately, not by default.
When is the right answer not to migrate at all?
When the app is a tangle nobody wants to touch. Lifting a poorly understood system to a new cloud as-is just moves the mess and adds a monthly bill. The better first project is often modernizing the workload where it sits or fixing the data layer before any provider enters the conversation. Migrating software you don't understand turns a clean lift-and-shift into a long archaeology dig.

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