Business Pill 34 · Revenue that is signed but not yet earned
A backlog is revenue that has been signed but not yet delivered. It is a promise of revenue, so it matters who made the promise.
A short explainer video. The numbers in it are round numbers for illustration.
The Short Answer
A backlog is revenue that has been signed but not yet delivered. A customer commits in a contract to buy a service over several years. The company has not earned that money yet, but it has been promised.
In company accounts this appears as remaining performance obligations: work the company still owes and expects to be paid for.
A Worked Example
The video uses round numbers. A cloud provider signs a five-year contract worth $10 billion. On day one, revenue is zero. The backlog is $10 billion. Each year, $2 billion moves out of the backlog and into revenue.

Why AI Backlogs Are Large
In AI, backlogs have grown very large. Computing capacity is scarce, so customers sign long contracts to be sure of getting it, and providers want those contracts.
What a Backlog Depends On
A backlog is only as good as two things: the customer’s ability to pay, and the provider’s ability to deliver. And if one customer makes up most of the backlog, the risk is concentrated.
The Order of Events
To deliver the backlog, the provider must first build the capacity. The spending comes first. The revenue comes later.
Three Questions to Ask
- Who signed these contracts?
- Can they pay?
- What must be built before the revenue arrives?
See It in the News
Applied Digital’s 250 MW Milestone and the Megawatt Gap. A news piece on signed capacity against capacity actually carrying load.
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