Add-on users
Each Solid Accounting tier includes a base number of users:
| Tier | Included users |
|---|---|
| Standard | 3 |
| Professional | 5 |
| Accountant | 10 |
If you need more, add-on users extend the seat count at $100 each, one-time (not annual). The cost applies to all tiers equally — adding a user to Standard, Pro, or Accountant is the same $100.
When add-ons make sense vs. tier upgrade
Math:
| Need | Cheapest path |
|---|---|
| 4 users on Standard | 1 add-on ($100) — total $449 vs Pro $499 |
| 5 users on Standard | 2 add-ons ($200) — total $549 vs Pro $499 (Pro wins) |
| 6 users on Pro | 1 add-on ($100) — total $599 |
| 11 users on Accountant | 1 add-on ($100) — total $799 |
| 15 users on Accountant | 5 add-ons ($500) — total $1,199 |
Generally: 3 or fewer add-ons is cheaper than upgrading a tier. Beyond that, the next tier is cheaper.
The non-price consideration: tier-specific features. Pro adds Payroll API, Ecommerce Hub, dimensions, multi-company. If you need those, upgrade to Pro regardless of add-on math. Accountant adds the Client Switcher, Accountant Copy advanced features, and white-label exports — relevant to bookkeepers managing multiple clients.
Buying add-ons
In Solid: Help → My Account → Add-on users → Purchase. Or at solidaccounting.com → My Account → Licenses → Add-on users.
The purchase:
- Charges your card on file
- Adds the seat count to your license immediately
- Takes effect on the next launch — no Solid restart needed
The new total user count is what your file's user picker enforces. After buying 2 add-ons on a Standard license, your file allows 5 concurrent users.
Removing seats
Add-ons are one-time purchases — you don't get refunded if you stop needing a seat. The seat stays with your license forever (until license transfer or termination).
If a user leaves the company:
- File → Manage Users → Deactivate User — removes their access to the file
- Their seat is freed (the seat count is the concurrent user limit, not the total ever limit)
- The next person you onboard takes that seat
The seat doesn't vanish; it gets reused. Add-ons accumulate over the life of the license.
Add-on users vs. multiple licenses
Some users wonder if they should buy a second license instead of more add-ons. Quick answer:
| Want | Better path |
|---|---|
More users on the same .solid file | Add-on users |
| Separate files per client (a bookkeeping firm) | Accountant tier (no add-ons needed; manages many clients on one license) |
| Separate files per business unit (multi-company) | Either Accountant tier with Multi-Company / Consolidation, or separate licenses per entity |
| One person needs to use multiple files at once | One license; the same Solid install can open multiple files |
Add-ons add seats to one license, one file. Multiple licenses are for legitimately separate organizations.
API access counts as a seat
If you have a long-running API integration (a Stripe webhook handler, a daily ETL pulling reports), the API key uses a seat the same way a human user does. Each API key is tied to a user record on the file; that user record consumes a seat.
For most integrations, this is a non-issue (one API key per integration is fine). For setups with many API integrations across many machines, factor the seat count.
Multi-user vs add-on users
Add-on users adds seats to a single file. For multi-file operations (multi-company, accountant managing clients), each file is its own seat-tracked entity. An accountant with 10 client files doesn't need 50 seats — each file's user count is independent.
Multi-user mode (Host Mode or Dedicated Server) is the technical way users connect; the seat count is the licensing constraint on top.
Common gotchas
"I bought an add-on but Solid still says I'm at the limit." Restart Solid Accounting on the host machine — license refresh happens at launch. If still wrong, log out and back in.
"I wanted to buy 5 add-ons but the form maxes out." Single transactions are capped at 10 add-ons. For larger purchases (a 30-person team's expansion), email support@solidaccounting.com to handle the invoice directly.
"Can I rent an add-on for one month?" No — add-ons are one-time purchases, not subscriptions. The pricing model is deliberately simple: one fixed cost per seat, no monthly billing complexity.
"I deactivated a user but my seat count didn't go up." Right — the seat count limit doesn't change. The deactivation frees one seat for someone else to use. The total seats your license has stays at base + add-ons forever.
"I'm switching from Pro to Accountant — what happens to my add-ons?" Add-ons stay with the license. Going from Pro (5 base + 3 add-on = 8) to Accountant (10 base + the same 3 add-ons = 13). The math typically works out neutral.
"Can I use add-ons across two different licenses?" No — add-ons are tied to one specific license. Each license has its own add-on count.
Cross-references
- Account & Billing overview — pricing model summary
- License keys — what a license entitles you to
- Multi-User module — how concurrent users actually work
- Pricing page — public pricing