Cloud storage is advertised on one number: the price per gigabyte per month. The bill that catches people out is a different number entirely, and it is not on the pricing page in the same size type.
What egress means
Egress is data leaving the provider’s network. Every download, every image served to a browser, every file an application reads back, every restore from backup - all of it is metered, and on most major platforms it is billed separately from storage.
The asymmetry is the striking part. Ingress - data going in - is almost always free. Storage has fallen in price for two decades. Egress has barely moved, which tells you something about which one is genuinely expensive to provide and which one is a commercial decision.
Why it surprises people
The cost scales with use, not with data. Storing 100 GB costs the same whether nobody touches it or a thousand people download it daily. A popular file costs more than an ignored one. So the bill rises exactly when things are going well, which is the worst possible time to discover a pricing surprise.
It is invisible until it is not. Nobody experiences egress during a proof-of-concept, because a handful of test downloads costs pennies. The number appears at scale, by which point the architecture is settled and moving is expensive.
Per-operation charges compound it. Many platforms bill per thousand requests as well as per gigabyte. A workload made of millions of small reads can generate a meaningful request bill even when the data volume looks modest.
Data gravity, and why it is not an accident
There is a name for the effect: data has gravity. Getting data in is free; getting it out costs. The larger your dataset grows, the more expensive leaving becomes.
That is a lock-in mechanism whether or not it was designed as one. A company with 50 TB in one provider is facing a five-figure bill simply to evaluate an alternative - before any engineering time, before any migration risk. Most do not bother, which is precisely the outcome the pricing structure produces.
Regulators have taken an interest. Some providers now waive egress charges for customers leaving entirely, under specific conditions and paperwork. That helps with the final exit and does nothing about the ordinary running cost of reading your own data.
Where it hurts most
Egress punishes specific, common patterns.
Serving media to end users. Every play, every image load, every download is a read. A modestly successful site can generate more egress cost than storage cost by an order of magnitude.
Backups you actually restore. Writing backups is cheap; the bill arrives on the day you have a disaster, which is exactly when you least want a procurement conversation. Our server backup guide treats restore cost as a first-class consideration for this reason.
Analytics that re-scan. Any pipeline reading the same dataset repeatedly pays repeatedly.
Multi-cloud anything. Data moving between providers is egress at both conceptual ends and billed at one.
Development and testing. Every engineer pulling a copy of production data is metered.
A worked example
Take a small media site. 500 GB stored, and 3 TB of downloads a month because people are actually watching the videos.
At a typical major-cloud rate of around $0.09 per GB egressed past a small free allowance, that 3 TB costs roughly $270 a month. The 500 GB of storage costs around $11.
So the storage bill is 4% of the total, and the number on the pricing page that you compared providers with was that 4%.
Now double the audience. Storage stays at $11. Egress goes to $540. Your costs scaled with your success, on a line item you never modelled, and the only lever available is to serve less data - which means degrading the product.
This is the shape of the problem. It is not that egress is expensive in absolute terms; it is that it is the variable you did not plan around, and it moves in the same direction as everything you want.
Questions worth asking a provider
Is egress billed at all, and at what rate past any free allowance? A provider that includes it says so plainly and prominently; one that does not tends to require three clicks and a calculator.
Are there separate per-operation charges? For workloads of many small files this can exceed the bandwidth cost.
What does a full restore cost? Take your backup size, multiply by the egress rate, and look at the number. If it is uncomfortable, that is information about your disaster recovery plan, not just your bill.
What does it cost to leave with everything? Calculate it now, while it is small.
How we price it
We do not charge egress. Plans are priced on storage alone - the free plan is 5 GB of total storage, and paid plans start at $3.99/month for 100 GB - so a file downloaded a thousand times costs exactly what one downloaded never does.
The practical benefit is predictability. Your bill is a function of what you keep, not of how popular it turned out to be, and you can share a large file widely without doing arithmetic first.
If you are sizing a plan, our guide to how much storage you actually need covers the estimating, and what free tiers really give you covers what to check before comparing any two providers on headline price alone.
