Free Desktop book-keeping software for small-businesses & freelancers
Kimai is a web-based multi-user time-tracking application
Profesionalna integracja z Krajowym Systemem e-Faktur (KSeF)
ERP Server
A super simple way to create & send invoices, receive payments online
Offline invoicing tool updated with latest GST rules
The Open Source Invoice Management Software
Free web-based invoicing primarily for Finnish companies