Guide
Invoicing software,
one-time purchase.
Not everything needs to be a subscription. Some invoicing tools let you pay once and use them forever. Here is what that looks like.
Last updated: June 4, 2026
How it works.
Most invoicing tools today charge monthly subscriptions: $10, $15, $30 per month, often per user. You rent access to the software. Stop paying, lose access.
One-time purchase invoicing tools work differently. You buy the software once and install it on your own server. You own the code. There is no recurring charge for using the software itself. Your only ongoing cost is server hosting.
This model is common for self-hosted PHP scripts sold on marketplaces like CodeCanyon, or directly by the developer. You get the source code, a license for one installation, and a support period.
Total cost over time.
| Period | One-time ($100 + $5/mo hosting) | SaaS ($15/mo) |
|---|---|---|
| After 6 months | $130 | $90 |
| After 1 year | $160 | $180 |
| After 2 years | $220 | $360 |
| After 3 years | $280 | $540 |
| After 5 years | $400 | $900 |
Illustrative example. Actual costs depend on the specific tool, hosting provider, and plan. The breakeven point is typically around 8-12 months.
What a one-time purchase includes.
Full source code
You receive the complete source code. Install it, modify it, extend it. The code runs on your server, not on the vendor's platform. If the vendor disappears tomorrow, your installation keeps working.
A license per installation
Most one-time purchase invoicing tools license per installation. One purchase covers one production server. If you need to run a second installation for a different business, you buy a second license.
A support window
Support and updates are typically included for a fixed period (6-12 months). After that, you can usually renew support separately, or continue using the software without active support.
No vendor lock-in
You own the code. If the vendor raises prices on future versions, you can keep running your current version. If you want to switch tools, your data is in a database you control. Export it anytime.
The tradeoffs.
You manage the server
Self-hosted means you handle hosting, backups, and security updates. For a simple PHP application on shared hosting, this is minimal. For complex setups with queue workers and Redis, it takes more effort.
Updates are manual
SaaS tools update automatically. Self-hosted tools require you to apply updates. Some tools include one-click updaters, but you still need to trigger them. This gives you control over timing but adds a step.
Higher upfront cost
A SaaS tool might cost $15 to start. A one-time purchase is $50-$200 upfront. The total cost is lower over time, but the initial outlay is higher. This matters if cash flow is tight in month one.
Who should consider it.
The one-time purchase model works well for freelancers, solo consultants, and small businesses who want predictable costs and data ownership. If you already have hosting (even shared hosting), the marginal cost of running invoicing software is near zero.
It works less well if you need integrated payment processing, native mobile apps, or want someone else to manage the infrastructure entirely.
InvoiceScript uses this model. One purchase, full source code, runs on PHP with SQLite or MySQL. See pricing or try the demo.
One-time purchase
Pay once. Use forever.
No monthly fees. No per-user charges. Full source code on your server.