Conference Agenda

Session
G03: Enhancing VAT Collection in Africa: Evidence from Tax Administrative Data
Time:
Friday, 22/Aug/2025:
2:15pm - 4:15pm

Session Chair: Amina Ebrahim, UNU-WIDER
Discussant 1: Rodrigo Oliveira, UNU-WIDER
Discussant 2: Amina Ebrahim, UNU-WIDER
Discussant 3: Adrienne Forder Lees, Institute of Development Studies
Location: SS6


Presentations
2:15pm - 2:37pm

Beyond The Tax Bill: Measuring Tax Compliance Costs For Ugandan Firms

Adrienne Forder Lees1,2

1Institute of Development Studies, United Kingdom; 2University of Sussex, United Kingdom

For low-income countries looking to enhance revenue mobilisation without harming firm growth, understanding the full burden of taxation, beyond just tax liabilities, is crucial. This paper documents the substantial and often regressive tax compliance costs faced by small and medium-sized firms in Uganda. Using original survey data from nearly 2,000 firms, matched to administrative tax data, I show that compliance costs are significant, equivalent to 2% of turnover for the median firm. Moreover, total compliance costs often exceed firms' tax liabilities. Breaking down cost components, I find that labour time spent on tax compliance activities is the largest component, with tax compliance consuming a median of 34 hours of labour time per month, and approximately 20% of firm owners' working hours. Using a survey experiment, I test how sensitive compliance costs measures are to the measurement strategy, finding significant divergence between estimates from an itemised module versus more aggregate questions.

Lees-Beyond The Tax Bill-120.pdf


2:37pm - 3:00pm

Climate Shocks and Economic Resilience: Evidence from Zambia’s Formal Sector

Rodrigo Oliveira1, Kwabena Adu-Ababio1, Evaristo Mwale2

1UNU-WIDER, Finland; 2Zambia Revenue Authority

Low-income countries face the combined challenges of climate shocks and limited domestic revenue mobilization, yet these issues are rarely studied together. This paper provides new evidence on the impact of climate shocks on firm performance and tax revenue in a low income country context, using firm-level data from Zambia. We find that extreme weather events, such as excessive rainfall and high temperatures, significantly reduce firms’ sales, input purchases, and tax collection, particularly in sectors such as manufacturing, retail, accommodation, and construction. Firms respond by reducing employment and wages, reflecting a decline in productivity.

Oliveira-Climate Shocks and Economic Resilience-457.pdf


3:00pm - 3:22pm

Mapping VAT Non-Compliance in Rwanda

Amina Ebrahim1, Umuhire Grace Ingabire2, John Karangwa2

1UNU-WIDER; 2Rwanda Revenue Authority

Value Added Tax (VAT) collection is essential for achieving domestic revenue objectives. Yet, the extent of misreporting, or the VAT gap, is infrequently and unsystematically evaluated in developing countries, where it would be most beneficial. This study utilizes VAT declaration and audit data to estimate VAT misreporting in Rwanda, applying a machine learning approach to predict evasion in unaudited firms and periods. We measure the underreporting component of the compliance gap, quantifying potential revenue losses due to non-compliance. We estimate a 62 per cent VAT gap among all VAT-reporting enterprises in Rwanda. The Manufacturing and Wholesale and retail sectors have the highest VAT gaps.

Ebrahim-Mapping VAT Non-Compliance in Rwanda-272.pdf