Answers
Every question, answered.
The full question set behind Reserved Instances, renewals, coverage, and pricing: one page, one stable link per question. The same answers hold whether you're carrying one reservation or ten thousand.
Reservations, plainly
What a Reserved Instance actually is, the choices you make buying one, and the few ways AWS lets it flex.
- What exactly is an AWS Reserved Instance?
A Reserved Instance is a 1- or 3-year billing commitment that discounts matching usage automatically. It does not reserve physical capacity, and it does not provision anything. The discount applies when a running resource's attributes match the RI's. It stops when they stop matching. Reserver covers RIs for Amazon RDS, ElastiCache, and EC2 today. The real risks are the wrong term or class, and a term that lapses unrenewed.
- What's the difference between a 1-year and 3-year term, and No/Partial/All Upfront?
Term (1 or 3 years) and payment option (No, Partial, or All Upfront) set how deep a reservation's discount goes. A longer term and more cash upfront both buy a deeper discount. Neither changes what is eligible to be reserved. A 1-year No Upfront RI and a 3-year All Upfront RI on the same instance class cover the same usage. Only the price and the cash flow differ. The right mix depends on how sure you are that the instance family will still run in a few years. The discount numbers alone do not decide it.
- Should I buy a 1-year or a 3-year reservation?
A 3-year term usually discounts more than a 1-year term. It also locks you in three times as long. AWS never cancels a Reserved Instance early. Buy a 3-year term and stop the instance after 14 months, and you still pay for all 36. Run the numbers for your own instance type and horizon with the free Term Check tool.
- Should I pay All Upfront, Partial Upfront, or No Upfront?
All Upfront pays the whole term at purchase and reaches the deepest discount. No Upfront pays nothing at purchase and reaches the shallowest discount. Partial Upfront splits the two. Every option locks in the same non-cancellable term, so the choice only changes cash flow.
- Does a reservation have to match the exact instance size we're running?
Not always, because size flexibility lets one reservation cover several sizes in the same instance family. The discount applies proportionally across those sizes. EC2 Standard RIs get it at regional scope. RDS gets it on most engines, across Single-AZ and Multi-AZ. ElastiCache reserved nodes gained it in October 2024. The family itself never flexes. A reservation bought for the wrong family covers nothing, however flexible the size math is.
- Should we buy a Regional or a Zonal reservation?
Regional is the more flexible default, since its discount follows matching usage to any Availability Zone in the region. A Zonal RI pins the discount to one Availability Zone. For EC2 it also pins a real capacity reservation there. That only pays off when a workload cannot tolerate a capacity shortfall in one AZ. For most fleets, Regional's flexibility is worth more than Zonal's capacity guarantee.
- Standard or Convertible: which Reserved Instance type should we buy?
Buy Standard for the deeper discount, or Convertible (EC2 only) to keep the option to exchange mid-term. Standard fits a family with a stable track record. Convertible trades some discount depth for the right to exchange into a different family, size, OS, or tenancy. Across the full priced EC2 catalog, Convertible costs a median of about 15% more than Standard for the same instance, term, and payment option. RDS and ElastiCache have no Convertible option. On those two services the family and engine choice at purchase is final. A Standard EC2 RI can be resold on the RI Marketplace if the fleet outgrows it. A Convertible RI cannot.
Convertible costs a median of about 15% more than Standard for the same instance, term, and payment option. It pays off only when your real chance of changing this instance mid-term clears the break-even point. Run your own numbers with the free Convertible Check tool.
- What can I actually exchange a Convertible RI into?
A different family, instance size, operating system, or tenancy, all within EC2. AWS requires an exchange of equal or greater value. You can top up the difference in cash. An exchange never hands cash back. RDS and ElastiCache sell no Convertible class at all, so this exchange right only exists on EC2.
Renewals & lapses
AWS Reserved Instances never renew themselves. What that costs, why it slips, and the one way out of a term early.
- What happens when a reservation I own expires?
The instance keeps running, and its price returns to the on-demand rate at once. AWS does not renew a Reserved Instance for you. Reserver tracks each end date and flags the reservations that are close to it. Alert delivery and renewal autopilot are on the roadmap. Today you check the expiry radar and buy the renewal yourself.
- AWS can email me before a reservation expires. Why use Reserver?
The AWS alert is opt-in and off by default. It emails up to 10 addresses 7, 30, or 60 days ahead, and on the day. It only notifies. It does not say what to buy. Reserver shows every end date from every connected account on one screen, and flags the close ones. It then shows the replacement purchase with its break-even date and yearly saving. Reserver does not send the alert itself yet. Email delivery is on the roadmap. Our advice: turn the AWS alert on, and use Reserver to decide what to buy.
- Do AWS Reserved Instances renew automatically?
No, AWS Reserved Instances never renew themselves, on any of the three services Reserver covers. A renewal is a fresh purchase decision with its own term and payment option. Nothing in the AWS console prompts it. That is why it slips even on disciplined teams. Someone or something has to watch the calendar.
- What does one missed renewal actually cost?
The median priced reservation in Reserver's own AWS Price List catalog is worth about $1,484 a year. That is roughly $0.17 an hour, $4 a day, and $28 for a week left unnoticed, on a single reservation. A lapse of any length has a real price once you multiply by the reservations a fleet carries. That holds for one tracked reservation or thousands.
- Can we get out of a reservation we no longer need?
Only for EC2 Standard RIs, through the RI Marketplace, which resells the unused portion of the term. Convertible RIs and every RDS or ElastiCache reservation have no resale option. The safety valve exists for one type on one service. Use it when a family turns out to be short-lived. Do not plan a purchase around it from the start.
Coverage & how much to buy
The two numbers that tell you whether your reservations are doing their job, and the target that sits between under- and over-buying.
- What does "coverage" mean, exactly?
Coverage is the percentage of your reservable running capacity that is currently matched to a reservation you own. Anything below 100% pays the on-demand premium on usage that could be discounted. Coverage cannot exceed 100%. Extra reservations with no usage to match sit idle. It counts only usage that was ever eligible for a reservation. Workloads that could never be covered do not dilute the number.
- Should we aim for 100% coverage?
Usually not, because the right target sits below 100% and is sized to the stable part of the fleet. Reserving every last instance leaves no room for the fleet to shrink, resize, or retire. You would pay for capacity that is gone. Most teams do better to reserve the steady core and leave the volatile edge on-demand. Then they revisit the split as usage changes.
- Can a reservation actually cost more than just paying on-demand?
Yes, because below a certain utilization a reservation's own cost outweighs its discount and it loses money. This happens when the family it covers loses ground. The fleet gets smaller, moves to another region, or is decommissioned before the term ends. The reservation keeps billing full price while it discounts little or nothing. Coverage alone cannot see this failure, because it looks only at the fleet's side of the equation.
- Is there one number that tells us whether our reservations are actually working?
Effective Savings Rate (ESR) is the percentage saved off on-demand-equivalent cost, with coverage, discount depth, and utilization priced in. Two fleets can post the same coverage and land on very different ESR. Discount depth and utilization move it as much as coverage does. A renewal lapse shows up here too, priced in real points and dollars.
By fleet size
One account with ten reservations and an AWS Organization with ten thousand fail in different ways. Who owns the job, and what breaks first, at each size.
- I only have a handful of reservations, is Reserver worth it?
Yes, because Watch is free for one AWS account and any number of reservations. The median reservation in our AWS price data saves about $1,484 a year. Renew it 14 days late and you lose about $57. That loss is small, but on Watch it costs you nothing to prevent. At this size, most of the money is in instances that nobody reserved. On $3,000 a month of compute, that is about $10,530 a year at our conservative rates. If you add more accounts, Autopilot is a flat $149 a month, or $1,490 a year. The price does not change with the number of reservations.
- We run many AWS accounts. Does Reserver scale to that?
Yes. Scale is the plan for that. Connect every account you run and see them all in one coverage map. The price is a flat $499 a month, or $4,990 billed once a year, for all accounts. You connect each account individually today. We are still building one-stack AWS Organizations enumeration, SSO/SAML, and custom approval chains. Check the roadmap before you plan around them. If you need an MSA, a security review, or an SLA, Enterprise covers that paperwork. AWS Savings Plans are on the roadmap. They are not live yet.
- Who should own reservations when we only have 1–10, on a single account?
Usually a founder or the first platform hire, who tracks it alongside everything else. The first thing to break is the renewal nobody put on a calendar. A term ends with no warning and usage reverts to on-demand. With no dedicated owner, nobody notices for weeks. A mistake at this size is cheap in absolute terms. It is still expensive next to the tool that would have caught it, and Watch, built for exactly this size, costs nothing.
- Who owns reservations once we have dozens across a few accounts?
Usually a platform or DevOps lead, with a finance counterpart reviewing the number on a schedule. The first thing to break is the gap between reviews. Coverage drifts in the weeks after a quarterly check closes, and nothing catches it until the next cycle. A mistake at this size is a slow build-up of small slippages across many reservations. It is harder to notice and just as costly in total.
- Who owns reservations across an AWS Organization with hundreds or thousands?
Usually FinOps or cloud economics, with procurement and security weighing in on access and approvals. The first thing to break is the seam between accounts. Each account can look fully covered alone while the org-wide picture hides a much bigger gap. Re-orgs also strand reservations tied to a team or account that no longer exists. A mistake at this size is invisible per account and very real in aggregate. The money hides where no single dashboard looks.
- How much time does this actually save?
A Growth-size fleet spends about 39 hours a year tracking reservations by hand. That is $3,705 at a fully loaded rate, split across quarterly reviews, cross-account reconciliation, and purchase decisions. That's about 2× what Autopilot costs a year. Reserver gives back most of that time. A person still approves each purchase.
- Does a Reserved Instance discount apply across all my AWS accounts?
Yes, by default, because AWS shares a Reserved Instance or Savings Plans discount across the whole consolidated bill. That includes accounts that did not buy it. A per-account coverage number can therefore be wrong in either direction. The discount your account measures might belong to a reservation in a different account. A Zonal RI is the one exception, because it never shares. Left unnoticed for a month, one reservation's lost discount costs about $403, at the same illustrative on-demand rate used elsewhere on this site.
Pricing & value
Flat price, every tier, unlimited reservations. What that means for the bill and how fast it pays for itself.
- Do you take a percentage of my savings?
No, never. Reserver is a flat price, billed monthly or annually. With percentage-of-savings pricing, the vendor earns the most when your bill was the worst. We charge a fixed price for the software.
- We already use Cost Explorer's recommendations. Why Reserver?
Cost Explorer gives you a number. You then check it across three consoles by hand. Reserver matches each reservation to a running instance and shows the math. It flags gaps and expiries, and it tells you what to buy next.
- Is Watch really free forever, or is that an early-access price?
Forever. Watch covers one AWS account, unlimited reservations, and the full coverage map and expiry radar. It is not a trial, and the price does not expire. A paid plan adds more connected accounts, utilization sampling, a notification channel, and team roles. Automated purchasing is not live on any plan yet.
- Do you charge per reservation, or per instance?
No. Every Reserver plan covers unlimited reservations, from one to tens of thousands. Pricing scales with connected AWS accounts and automation depth, never with how many reservations you have or how much you save.
- What happens to our price when we connect more AWS accounts?
Nothing changes until you cross a plan's account limit. Watch covers 1 account and Autopilot up to 5. Scale covers an unlimited number for one flat $499 a month, or $4,990 billed once a year. You add each account yourself today, and one-stack AWS Organizations enumeration is on the roadmap. No per-account surcharge, no renegotiation.
- Do log archive and audit accounts count toward our plan?
Only if you connect them. A plan counts connected AWS accounts. Connect each account that runs RDS, ElastiCache, or EC2, and the account that buys your reservations. A Log Archive or Audit account usually needs neither. Read which accounts to connect.
- Why is Enterprise still a custom quote instead of a published price?
Because Enterprise is Scale plus the paperwork some procurement teams need before anyone connects an account. That means a master service agreement, a security review, an SLA with a named contact, and private commercial terms. These vary enough by customer that a single number would overcharge most of them or undercharge the rest.
- How fast does Reserver actually pay for itself?
Autopilot's flat $149/month typically pays for itself in about 7 days on the growth-fleet numbers used on this site. That figure moves with your own spend and coverage. The savings calculator on the pricing page runs the same math on a number you type in, instead of a stock example. Watch has no payback period to clear, because it is free.
Security, access & procurement
What the read-only role can see, what the planned purchase role will touch, and what procurement asks for before either gets connected.
- Does Reserver need write access to my AWS account?
No. Reserver uses a read-only IAM role limited to Describe/List calls for RDS, ElastiCache, and EC2. It cannot change your workloads, data, or networking. A separate purchase role is on the roadmap. When it ships, it will be opt-in, narrowly scoped, and revocable. More in our security model.
- What can the read-only role actually do?
Nine named Describe/List calls, for RDS, ElastiCache, and EC2. No service-wide wildcards. It can read the shape of your fleet: instance types, regions, tags, reservation details, and nothing else. It cannot start, stop, modify, or delete anything.
- What will the purchase role be able to do?
The purchase role is not built yet. Reserver cannot buy anything today, on any plan. Once it ships, it will be a separate role scoped to the AWS reservation purchase APIs: rds:PurchaseReservedDBInstancesOffering and equivalents for ElastiCache and EC2. It will not be able to touch your running workloads, your data, or your networking.
- Can Reserver see our data, not just our infrastructure metadata?
No. Reserver reads infrastructure metadata used for matching: instance classes, regions, engines, reservation terms. Never database contents, cache values, or application data.
- Is our data isolated from other customers?
Yes. Every record is scoped to your organization. Access from another organization returns not-found. No permissions check exists there that someone could misconfigure.
- How do you access our AWS accounts? Do you store credentials?
Cross-account access is assume-role only, using the role you created and can revoke. We never see or store your AWS access keys.
- Can something buy a reservation without our sign-off?
Nothing can buy anything today, on any plan. No purchase role exists yet, so there is no automatic buying to configure. Once Autopilot ships, each rule will be able to require an approval step before a purchase runs. Every purchase will be logged with who, what, and when.
- Are you SOC 2 or ISO 27001 certified?
Not yet. Reserver is pre-launch. Formal certifications are on the roadmap; we'd rather say that plainly than claim something we can't back up.
- Do the free tools upload our data anywhere?
No, every free tool parses, matches, and prices what you paste entirely in your browser. The Coverage Check fetches one small, public price list from this site on your first Analyze. Every other free tool, including the Expiry Check, makes no network request at all. Nothing typed or pasted into any of the eight free tools is ever sent to a server. None of them needs a signup.
Scope & roadmap
RDS, ElastiCache, and EC2 ship today. Savings Plans, OpenSearch, Redshift, and other clouds are on the roadmap. They are not live today.
- Can Reserver buy reservations for me today?
Not yet. Reserver already finds the recommendation and shows the math. It does not execute the purchase today. Reserver is still building one-click purchasing, renewal autopilot, scheduled purchases, and age-based rules. We ship the read-only product well first, on purpose. See what is live and what is next on the roadmap.
- Which AWS services are covered?
Reserved Instances for Amazon RDS, ElastiCache, and EC2 at launch. Savings Plans, OpenSearch, Redshift, and other reservable services are on the roadmap.
- Does Reserver work with Azure or Google Cloud?
No. Reserver is AWS-only today. It covers Reserved Instances for Amazon RDS, ElastiCache, and EC2. If your company also runs Azure or Google Cloud, you can still use Reserver for the AWS part. The renewal rules differ by cloud: Azure reservations auto-renew by default, and Google Cloud's resource-based CUDs are opt-in. AWS has no auto-renewal at all. A habit learned on either of the other two clouds is exactly backwards on AWS. See our multi-cloud renewal comparison for the vendor-sourced breakdown.
- Does Reserver support AWS Savings Plans?
Not yet, because Savings Plans are still on the roadmap. A Savings Plan is a spend-based commitment instead of an instance-shaped one, so it needs its own matching logic. We would rather ship RIs for RDS, ElastiCache, and EC2 well than claim Savings Plans support before it is real.
- What about OpenSearch or Redshift reservations?
Not yet, because only RDS, ElastiCache, and EC2 ship today and OpenSearch and Redshift are on the roadmap. Both have their own reservation mechanics. Each needs the same care the first three services got before it is worth shipping. If either one holds up a decision to connect an account, the waitlist is the way to hear when it lands.
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