Simple Invoice vs Wave

Wave's free plan is a front door: invoicing and accounting cost nothing, and the business earns when clients pay by card through the invoice or when you add payroll or paid features. That is a legitimate model, and it means the free features are real rather than a trial. Simple Invoice is free because there is nothing to charge for — a static app with no account, no storage bill and no upgrade to sell. The difference shows in what each is optimised for: Wave's free tier is designed to make online payment the natural next step; Simple Invoice has no next step. Free vs paid invoicing software discusses the two kinds of free in general.

Wave's largest advantage is that the free plan includes bookkeeping. Invoices post to income, payments are recorded against them, expenses can be entered or scanned, and profit-and-loss and balance-sheet reports are generated from the ledger. For a sole trader who has never kept books, that is a complete system at no cost. Simple Invoice has none of it: it keeps one document in the editor and does not track statuses or invoice history. If you want accounts, Wave gives them; if you only need to make a document, Simple Invoice stays lighter.

Here the local tool has the edge. Simple Invoice's invoices are assembled from blocks you choose and configure, with six presets, several typefaces, colour and table styles and paper size; the design is saved as a template and applied to every invoice. Currency and date formats follow an ISO code and a locale per invoice, which matters when clients are in different countries. Wave offers a few templates with a logo and an accent colour — presentable, but fixed in structure. How to add a logo to an invoice shows how the header block handles branding.

With Wave, your clients' names, addresses and payment history sit on the vendor's servers under your account and their terms; the upside is automatic backup and access from any device. With Simple Invoice, that data is in one browser on one device — private by construction, and yours to export as JSON whenever you like. The cost is discipline: if the browser is cleared without a backup, nothing can recover it. Wave also works only online; Simple Invoice keeps working after the first load with no connection.

Wave's service is offered to businesses based in particular countries — the United States and Canada at the time of checking — so a freelancer elsewhere may not be able to open an account at all. A static browser app has no such restriction: it runs wherever a browser does, formats money for any currency and locale, and does not need to know where you are based. Check Wave's current availability for your country before comparing further.

Take Wave if you want bookkeeping included, expect clients to pay by card from the invoice, and are comfortable with a hosted account. Take Simple Invoice if you want the invoice produced quickly and exactly as you designed it, with nothing stored anywhere but your own machine, and you handle books and payments elsewhere. The two are not exclusive: some people design and send invoices from Simple Invoice and record the totals in Wave's ledger by hand.