This multi‑year digital transformation modernizes tax services, improves compliance, drives sustainable revenue and sustains Indonesia’s Directorate General of Taxes (DGT) for efficient tax organization based on data-driven decisions. The system processes millions of tax transactions daily, aligning Indonesia with the world’s most advanced digital tax administrations.
Qualysoft GmbH, the Vienna-based international IT consultancy organization announces the successful completion of Indonesia’s national Core Tax Administration System (CTAS) modernization program for the Directorate General of Taxes (DGT) under the Ministry of Finance. This multi‑year initiative delivers a modern digital foundation for taxpayer services, compliance, and revenue integrity and transparency at national scale.
CTAS went live on 1 January 2025, serving Indonesia’s population of over 270 million people. Since go-live, the system has been processing millions of tax transactions daily across a broad range of tax types including VAT, Corporate Income Tax, Personal Income Tax, Excise, and Property Tax. It is now the operational backbone of the Indonesian government’s national revenue collection.
The program concludes a five-year engagement spanning planning, full-scale system development, nationwide implementation, and a full year of live operations. The completion milestone in March 2026 marks the transition to the next phase focused on governance, annual technical support, and continuous enhancements.
Indonesia’s previous tax administration infrastructure dated to 2014, and despite consistent economic growth, the country faced a structural gap in domestic revenue mobilization. Manual, paper-based workflows, siloed legacy systems, and limited taxpayer self-service capabilities constrained both compliance rates and collection efficiency.
This modernization program was initiated in 2021 within a consortium between Qualysoft and LG CNS (infrastructure and quality assurance), the Core Tax Administration System (CTAS) is composed of two core components:
• A Core CTAS System, the central processing backbone for the tax authority;
a Web Taxpayer Portal that enables secure self‑service for registration, taxpayer education, filing, payments, and access to tax notices and documents.
• CTAS is built on a fully modular, microservice-based architecture using .NET Core, Angular, Docker, Kubernetes, and a hybrid relational and NoSQL data layer. The platform integrates with Indonesia’s national payment system, population registry, customs authority, and a broad ecosystem of third-party financial institutions via OpenAPI and REST interfaces.
Built on a microservices and API‑first architecture, CTAS integrates with banks, payment gateways, national ID services, customs, and partner institutions, allowing secure data exchange and coordinated compliance. The platform emphasizes transparency and performance, featuring end‑to‑end audit trails, risk‑based assessment and audit support, and role‑based access controls.
A defining strategic goal was government self-sufficiency. Through Qualysoft’s three design engines — all with graphical, no-code interfaces — DGT officials can independently introduce new tax types, amend business rules, configure audit workflows, and publish legally required forms and notices, without engaging any external vendor.
The program drew on international best practices, with collaboration involving the International Monetary Fund (IMF) in statistical analysis, risk methods, and data exchange approaches. Training and knowledge transfer were embedded across delivery phases to strengthen organizational and technical capacity.
The CTAS Taxpayer Portal gives all Indonesian citizens and businesses direct online access to their tax records, outstanding liabilities, and filing history. Electronic filing for VAT, income taxes, and other obligations can now be completed from home or office. Tax notices and official documents are delivered digitally. Refund claims and dispute resolution are managed within the platform, reducing processing times and administrative burden significantly.
Key outcomes include:
• Simplified taxpayer experience: Online registration, filing, and payments with clear notices and digital records.
• Enhanced compliance: Risk‑based selection, automated assessments, and improved case/audit management.
• Reduced administrative burden and operational efficiency: Paperless, standardized processes and integrated analytics streamline administration.
• Future‑ready governance: In‑house configuration of forms, workflows, and templates accelerates legal and policy updates.
The conclusion of the CTAS program in March 2026 is a significant milestone and a bridge to the next phase of Indonesia’s digital fiscal transformation. Upcoming priorities include the development of a Governance and Audit Technology System (ATS), continuous platform enhancements, ensuring that the platform remains secure, compliant, and responsive to Indonesia’s fiscal priorities.
Qualysoft remains a committed partner to Indonesia’s fiscal modernization journey to enhance the efficiency, transparency, and cost-effectiveness of tax administration, leading to increased tax revenue and reduced compliance costs.
