The short version
- The thing that stopped our campaign was a plan quota. A free email tier capped sends at 300 a day, and the software was capable of every part of what we had designed.
- Quotas are volume-triggered. Setup and test sends run underneath them, so the cap only lands once the real list runs.
- Find the number on every tool before the creative exists. A quota changes the sequence, and a sequence is cheap to change before anything is built on top of it.
Every tool in a marketing stack has a ceiling, and the ceiling is a number on the plan. Ours was a free email tier that capped sends at 300 a day. We found it during the send.
What is a tool ceiling?
A quota on your plan. Sends per day, contacts stored, automation runs per month, API calls per minute, seats, gigabytes. The software does everything you designed, a fixed number of times per day.
The quota that stopped us was a daily one. A monthly allowance answers a question about whether the campaign fits at all. A daily one governs whether today’s send finishes today.
A free tier has a second problem. Nothing about it goes through procurement. There is no invoice to justify and no contract to review.
The ceilings worth writing down before a campaign is designed:
| Layer | The number to write down |
|---|---|
| Email sending | Sends per day, separately from sends per month |
| Contact storage | Billable contacts, and what counts as billable |
| Automation runs | Tasks or operations included per month |
| API access | Requests per minute and per day |
| Ad account | Daily spend cap and account spending limit |
| Seats | Named users included before the price changes |
| Asset storage | Files or gigabytes per account |
Why do quotas surface mid-campaign?
Because they are volume-triggered, and a campaign is the only moment volume arrives. Everything before launch runs at a scale the quota cannot see. The cap and the design do not meet until the design is finished and loaded with a real list.
A cap of 300 a day turns one send into a queue. A list larger than the cap goes out across more than one day, and every step timed from the send date starts on a different day for different people.
Which ceilings bite hardest?
The quiet ones. A refused import announces itself. Somebody sees an error and fixes it.
An integration that retries without alerting stops delivering data while reporting that everything is fine. This is why we alert on absence rather than on errors.
How do you audit a stack before planning?
One table, two columns that matter. Every tool the campaign touches with its quota on one side, and the volume the campaign will actually generate against that quota on the other. Where the demand column is bigger, the design changes now rather than during the run.
Not every number is on the pricing page. Daily caps and rate limits tend to live in developer documentation or a fair-use page, and some exist only in a support reply, which is a good reason to ask in writing.
Do this before the creative. A 300-a-day cap points at a different sequence or a different tool, and either one is an ordinary decision while the campaign is still a document.
The cap was 300 a day. We found it during the send.
What do you do when you hit one mid-flight?
Stop the run rather than let it drain, so that the remainder is a known quantity rather than a partial send nobody can account for later.
Then there are two ways out. Pay for the tier that clears the quota, or re-cut the sequence to fit the tier you have. Neither one is the campaign that was signed off, so the client hears about it with the number and the two options.
The neighbouring failures worth auditing at the same time are integrations that break without erroring and naming every gate in week one.
Frequently asked questions
What is a daily send limit on an email marketing plan?
A cap on how many messages your tier will send in 24 hours, separate from the monthly total. One free tier we worked with capped sends at 300 a day. Check the daily figure, because a monthly allowance that looks generous can sit on top of a daily cap that decides whether today's send finishes today.
Why do marketing tools fail in the middle of a campaign rather than during setup?
Because plan limits are volume-triggered. Setup and test sends run at a volume the quota cannot see, and so does the first slice of a list. The cap only lands once real volume runs through it, which is always after the work has been committed.
Which tool limits should you check before launching a campaign?
Sends per day and per month, billable contact count, automation runs or tasks per month, API requests per minute and per day, named seats, and asset storage. Write each number next to the volume the campaign will produce against it.
How do you find the real limits on a SaaS plan?
Read the pricing page as a specification rather than a comparison, then check the vendor's rate-limit and fair-use documentation, which usually sits outside the pricing page. If a number is missing, ask support in writing, so the answer can be quoted later.
What should you do when you hit a sending limit mid-campaign?
Stop the run instead of letting it drain into a partial send, so the remainder stays a known quantity. Then tell the client, with the number and the two options: pay for the tier that clears the quota, or re-cut the sequence to fit the one you have.
Does upgrading a plan lift a limit immediately?
Not always. Seats and send caps generally move with the plan. Rate limits and sending reputation protect the vendor's own infrastructure rather than price the plan, so an upgrade does not necessarily change them. Check the specific limit before assuming the invoice fixes it.
Sources
- Chua Network delivery data across 8 client accounts (internal fact bank)
- Chua Network engagement records, anonymized (internal experience bank)
