Before writing this piece, I went back to my 2014 tax records to see how I filed my income tax return at that time. It was all on paper, eleven pages of complicated forms and several printed tax certificates. Everything tucked away inside a thick, heavy binder labelled “Tax returns” and neatly stored in the basement. A small time-capsule of a pre-digital era, and a reminder of what bureaucracy once rhymed with.
It is easy to forget how time consuming that process was, and how much paper and effort it required. Collecting the necessary information, filling in the forms, ticking all the right boxes, flicking through pages of printed instructions, and then making a (paper) copy and finally posting the return at the post office or dropping it off at the tax office in person.
Today, the reality in many jurisdictions is very different. Most taxpayers will go online, log in with a government-issued user ID, and access a pre-filled return populated with third-party data. Guidance is built directly into the system, signatures are electronic, and after pressing “send”, the entire return is delivered in a second and simultaneously stored digitally in the tax administration’s portal.
Tax administration has transformed dramatically over the past decade and in our latest analysis, we get to take a closer look at just how far we’ve come, and where progress is still needed.
A 10-year perspective on the evolution of tax administration
Looking at more than 50 tax administrations, the OECD’s annual Tax Administration report presents internationally comparative data on tax systems and their administration, and traditionally focuses on performance-related data and ratios from the most recent available fiscal year. The 2025 edition, however, adds a 10-year perspective on how tax administration has evolved since 2014. It shows is that:
- Tax administrations remain central to government revenue collection: Net collections by tax administrations average 63% of total government revenue, an increase of almost 8 percentage points since 2014. They continue to be the principal government revenue collection agency in three-quarters of jurisdictions covered in the report.
- There is a structural shift towards self-service channels: The data shows a move away from in-person contact during office hours to digital channels that can be used 24/7. In fact, since 2014, in-person contacts declined by 56%, while online contacts have tripled since 2018 to more than 3 billion contacts in 2023.
- Filing tax returns electronically has become the norm: Over the last decade, e-filing rates have increased significantly – between 18 and 24 percentage points – across the main tax types. In 2023, close to 90% of personal income tax returns were filed electronically. The share is even greater for corporate income tax (96%) and value added tax (99%).
- Revenue collections grow faster than tax arrears: Outstanding arrears totalled around EUR 2.7 trillion at the end of fiscal year 2023. While this is a significant increase from the EUR 1.5 trillion reported in 2014, the average ratio of fiscal year-end arrears to net revenue collections has declined since then by around 10%.
- Technology helps fewer staff to serve more taxpayers: With population and labour forces growing, 60% of administrations report declining staff numbers, meaning that the remaining staff are having to serve more people. On average the population and labour force per full-time employee increased by around 15% between 2014 and 2023, highlighting the impact of digital tools and artificial intelligence (AI) in maintaining service levels.
The digital revolution is still unfolding
Tax administration today looks nothing like it did ten years ago, and yet the transformation is far from complete. The rapid rise in the use of AI is one of the clearest signs of this ongoing change.
In recent years, the use of AI has skyrocketed. In 2016, only 9% of tax administrations reported using AI and by 2023, that figure rose to 69%, with another 24% reporting they are in the process of implementation (see Figure 1).
Also, in this latest edition of Tax Administration 2025, around 25% of the examples submitted by administrations related to AI, illustrating just how widely it is being deployed.
AI is now used across a broad range of functions in tax administrations – from supporting analytical work, to providing faster and more efficient services to taxpayers, or to improving case work selection. In addition, AI is automating high volume repetitive tasks, allowing tax administration staff to focus their expertise on more complex issues that require human judgement.
As technology continues to evolve, so too will the ways in which taxpayers interact with their administrations. Somewhere in a basement, the old tax folder still sits on a shelf gathering dust as a quiet reminder of how far tax administration has come, and how much further this digital revolution will take us.
For further reading, access Tax Administration 2025.
More on the data
Since 2004, the OECD has been publishing internationally comparable data on aspects of tax systems and their administration through the Tax Administration Series, but this is only one of the OECD’s Forum on Tax Administration (FTA) outputs. Please visit our webpages for more information on the Tax Administration Series and its underlying data collected through the International Survey on Revenue Administration, as well as or our other work, for example, on the Digital Transformation of Tax Administration, Maturity Models and the Inventory of Tax Technology Initiatives.
We also invite you to follow the live stream of the opening session of the OECD Forum on Tax Administration Plenary meeting on 18 November 2025.
