KoltrixPer-User vs Per-Workspace Email Pricing: Doing the Math
Per-user and per-workspace pricing look similar at three people and diverge fast after that. A worked way to compare the two models for your own team size.
On this page(8 sections)
Two email tools can quote you similar prices for a three-person team and very different prices for a twelve-person one. The difference usually isn't the headline rate; it's the pricing model underneath. Per-user and per-workspace pricing behave differently as you grow, add shared addresses or bring in part-time help.
This guide shows how each model works, where each one is cheaper, and how to run the comparison with your own numbers. We use variables instead of other vendors' prices, since those change. Plug in current figures from their pricing pages.
The two models
Per-user pricing charges a fixed amount for each person (or mailbox) every month. Ten users cost ten times one user. It's simple and predictable, and it's the most common model for business email.
Per-workspace pricing charges a fixed amount for the whole team, usually with a number of seats included, and sometimes a smaller charge for each seat beyond that. Limits like domains, addresses, storage and sending volume are attached to the plan rather than to each person.
Neither is inherently cheaper. It depends on your team's shape.
The basic formulas
Let:
n= number of people who need accessu= per-user price per monthW= per-workspace plan price per months= seats included in the workspace planx= price per extra seat beyonds
Then:
per-user monthly cost = n × u
per-workspace monthly cost = W + max(0, n − s) × x
That's the starting point. The interesting part is what goes into n.
What counts as a "user"?
This is where the models diverge in practice.
Shared addresses
Under some per-user setups, a shared mailbox like support@ needs its own license if you want it to be a real mailbox several people can log into. If you have three shared addresses, your effective n for per-user pricing is people plus three.
Under per-workspace plans, shared addresses typically count against an address limit rather than a seat, so they don't add to the per-person cost.
Part-timers and occasional users
A founder who answers support on Fridays, an accountant who needs billing@ once a month, a contractor for six weeks. Under per-user pricing, each one is a full license for as long as they have access. Under per-workspace pricing, they may fit inside included seats.
Growth spurts
Hiring two people in a month raises a per-user bill immediately. A per-workspace plan with spare included seats absorbs them until you pass the seat count.
A worked comparison
Here's a comparison using Koltrix's published prices as the per-workspace example, and a variable u for a generic per-user provider.
Koltrix Starter: W = $12, s = 3, x = $4. Koltrix Pro: W = $39, s = 10, x = $4.
| Team size | Per-user cost | Koltrix Starter | Koltrix Pro |
|---|---|---|---|
| 2 people | 2u | $12 | $39 |
| 3 people | 3u | $12 | $39 |
| 5 people | 5u | $20 | $39 |
| 8 people | 8u | $32 | $39 |
| 10 people | 10u | $40 | $39 |
| 15 people | 15u | $60 | $59 |
Add shared-address licenses to the per-user column if your provider requires them.
To find the break-even for any per-user price, solve n × u = W + max(0, n − s) × x for n. If u is above x (the extra-seat price), per-workspace pricing gets relatively cheaper with every person you add beyond the included seats.
The plans also differ in limits. Starter includes 2 domains, 10 addresses and 10,000 API sends a month; Pro includes 10 domains, 50 addresses and 50,000 API sends. A five-person team might pick Pro for the limits, not the seats. Current figures are on our pricing page.
It's not only about price per person
A fair comparison also counts what each price includes.
Bundled software. Many per-user business email plans include documents, spreadsheets, calendars, video calls and storage. If you use those, part of the per-user price is paying for genuinely useful software, and you'd need to buy it elsewhere if you switched.
Product email. Some per-workspace tools, Koltrix included, bundle a transactional email API for your app. Per-user mailbox providers generally don't, so you'd add a separate sending vendor.
Limits. Workspace plans cap domains, addresses, storage or sending volume. Check that your needs fit, or the cheaper plan becomes the wrong plan.
Three team shapes, three different answers
The tight founding team. Three people, one domain, one or two shared addresses, everyone full time. The models come out close. Choose on features, not pricing structure.
The growing team with helpers. Six full-time people, a part-time support contractor, an outside bookkeeper who needs billing@, and four shared addresses. Here per-user pricing can count eleven or more licenses while a workspace plan counts seven seats. The difference is mostly people and addresses who barely log in.
The suite-dependent team. Ten people who live in shared documents, calendars and video calls every day. A per-user business suite is probably the right answer even if a workspace email plan is cheaper on paper, because you'd be paying for those tools somewhere else anyway.
Questions to ask before switching models
- How many people really need daily access? How many need occasional access?
- How many shared addresses do you need, and do they cost a license today?
- Do you use bundled productivity apps that you'd have to replace?
- Do you pay separately for app sending that a workspace plan could include?
- What are the plan limits, and how close are you to them?
- How will the cost change if you double the team in the next 18 months?
Key takeaways
- Per-user pricing scales linearly with people; per-workspace pricing is flat until you pass included seats.
- Shared addresses and occasional users are where per-user costs quietly grow.
- Compare what each price includes, from office apps to app sending, not just the headline rate.
- Run the formula with your own team size today and in 18 months before deciding.
Start with Koltrix
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