Product development
Small business shouldn't have to organize its day around invoicing software. The software should adapt to the way the business sells, collects payments, and collaborates with its accountant.
For entrepreneurs and organizations
By industry
For collaboration
Odaberite sučelje koje odgovara uslugama koje koristite.
Resources
Practical Guides, news, customer experience and security facts for decisions about invoicing, fiscalization, POS and eCommerce.
Resources
Practical Guides, news, customer experience and security facts for decisions about invoicing, fiscalization, POS and eCommerce.
Resources
Practical guides, news, user experiences and security facts for accounts, fiscalisation, POS and eCommerce decisions.
Product development
Small business shouldn't have to organize its day around invoicing software. The software should adapt to the way the business sells, collects payments, and collaborates with its accountant.
Billing and invoicing
A sale is only complete when payment and invoicing are settled. BillKO connects these steps to reduce manual data entry and provide a clearer status for every sale.
Product development
Small business shouldn't have to organize its day around invoicing software. The software should adapt to the way the business sells, collects payments, and collaborates with its accountant.
Billing and invoicing
A sale is only complete when payment and invoicing are settled. BillKO connects these steps to reduce manual data entry and provide a clearer status for every sale.
Product development
Small business shouldn't have to organize its day around invoicing software. The software should adapt to the way the business sells, collects payments, and collaborates with its accountant.
Billing and invoicing
A sale is only complete when payment and invoicing are settled. BillKO connects these steps to reduce manual data entry and provide a clearer status for every sale.
Short quotations and stories show how BillKO works for invoicing, POS, eCommerce and accountants.
CERTIFIED SYSTEM
Information security management
SIQ • CERTIFICATE
Certificate for management system
KUPUJ ONLINE d.o.o.
Fiorella La Guardie 13, 51000 Rijeka, Croatia
Development, delivery and maintenance of digital products
Information Security Records, Declaration of Applicability (SoA) 2025, version 1.0 of October 28, 2025
appropriately applies and maintains a management system that meets the requirements of the standard
ISO/IEC 27001:2022
Certificate number
I-0192
Date of certification
2025-10-30
Edition
01 / 2025.10-30
Valid until:
2028-10-30
SIQ Ljubljana · Mašera-Spasićeva street 10, 1000 Ljubljana, Slovenia

CERTIFIED SYSTEM
Information security management
SIQ • CERTIFICATE
Certificate for management system
KUPUJ ONLINE d.o.o.
Fiorella La Guardie 13, 51000 Rijeka, Croatia
Development, delivery and maintenance of digital products
Information Security Records, Declaration of Applicability (SoA) 2025, version 1.0 of October 28, 2025
appropriately applies and maintains a management system that meets the requirements of the standard
ISO/IEC 27001:2022
Certificate number
I-0192
Date of certification
2025-10-30
Edition
01 / 2025.10-30
Valid until:
2028-10-30
SIQ Ljubljana · Mašera-Spasićeva street 10, 1000 Ljubljana, Slovenia

Information security management
SIQ • CERTIFICATE
Certificate for management system
KUPUJ ONLINE d.o.o.
Fiorella La Guardie 13, 51000 Rijeka, Croatia
Development, delivery and maintenance of digital products
Information Security Records, Declaration of Applicability (SoA) 2025, version 1.0 of October 28, 2025
appropriately applies and maintains a management system that meets the requirements of the standard
ISO/IEC 27001:2022
Certificate number
I-0192
Date of certification
2025-10-30
Edition
01 / 2025.10-30
Valid until:
2028-10-30
SIQ Ljubljana · Mašera-Spasićeva street 10, 1000 Ljubljana, Slovenia

Tell us how you issue invoices, get paid or sell, and we will guide you to the most useful next step.
Tell us how you issue invoices, get paid or sell, and we will guide you to the most useful next step.
Tell us how you issue invoices, get paid or sell, and we will guide you to the most useful next step.