Abstract
The purpose of the article is to assess the effectiveness of the digital transformation of tax administration in the Republic of Kazakhstan in the context of global trends and to develop a three-level model of digital maturity to reduce the tax gap. The study employs comparative analysis (drawing on the experiences of Estonia, Poland, and the UAE), statistical modeling of fiscal effects, and the OECD methodology (Tax Administration Maturity Model). The theoretical framework is based on the Tax Administration 3.0 concept. An adaptive digital maturity model (2026–2030) has been developed, incorporating automated verification, predictive analytics, and proactive service. It has been established that the technological maturity of the infrastructure is a more significant factor in compliance than the tax rate. This study is the first to adapt the principles of “embedded” taxation to the specific parameters of Kazakhstan’s 2026 tax reform, proposing a quantitative estimate of the fiscal effect at 4–7 trillion tenge annually.