New Delhi, Oct. 1 -- Central and state governments collected Rs.1.89 trillion in goods and services tax (GST) before refunds in September, a robust 9.1% improvement over the year-ago period, official data showed on Wednesday.

Gross GST collections in September grew faster than the 6.5% increase in August even though a slowdown in sales was anticipated ahead of rate changes last month.

After refunds to both domestic businesses and exporters, the net GST collection stood at Rs.1.6 trillion in September, a 5% annual jump. Total tax refunds in September stood at Rs.28,657 crore, 40% more than the refunds issued at the same time a year ago.

September GST collections pertain to sales made in August and do not reflect the impact of GST rate c...