SimplyBook.me offers online booking with basic invoicing features. Below is a curated list of 20 free invoicing tools that can replace its invoicing capabilities while providing robust billing, expense tracking, and client management—all at no cost.
Get targeted exposure with custom position pinning and highlighted placement.
Open‑source invoicing platform with unlimited invoices, quotes, payments, and time‑tracking for freelancers and small businesses.
Full‑featured free accounting suite with invoicing, receipt scanning, and bank reconciliation for small businesses.
Free tier for up to 5 customers; includes professional invoices, recurring billing, and multi‑currency support.
Create and send invoices directly from PayPal; recipients can pay instantly using their PayPal balance or cards.
Free invoicing tool integrated with Square payments; supports customizable templates and automatic reminders.
Free plan allows unlimited invoices, estimates, and basic reporting for up to 3 clients.
Simple invoicing with unlimited invoices, basic reporting, and time tracking for freelancers.
Free for up to 5 users; includes invoicing, time tracking, and project management in one dashboard.
Time‑tracking and invoicing solution; free tier supports a single user with unlimited invoices.
Open‑source accounting software with free invoicing, expense management, and multi‑currency support.
Self‑hosted PHP application for creating and managing invoices, quotes, and payments.
Lightweight, open‑source invoicing system that runs on PHP/MySQL; ideal for small operations.
Free desktop accounting software with invoicing, expense tracking, and double‑entry bookkeeping.
UK‑focused free accounting tool offering invoicing, expense tracking, and basic reporting.
Free online invoicing with automated data entry via MagicBot, multi‑currency invoices, and tax support.
Open‑source invoicing and accounting suite for small businesses, supporting multiple languages and currencies.
Free, open‑source ERP with an invoicing module; includes customizable templates and integration with sales orders.
Free tier for sole traders; provides basic invoicing, expense tracking, and VAT reporting.
Offers a free starter plan for freelancers with unlimited invoices and basic reporting.
Deploy the open‑source version on your own server for complete control; includes unlimited invoices, clients, and projects.