India collected more revenue from its goods and services tax in April than any month since it was implemented in 2017, a sign that companies are adjusting to the tax after a troubled start.

Authorities brought in 1.14 trillion rupees ($16.4 billion) in April, about 10 percent above the amount in April 2018, the Finance Ministry said May 1. It was also 16 percent above the monthly average collections in the 2018-19 financial year, which ended in March.

Underwhelming collections under GST have been a source of concern to Indian tax authorities, prompting them to take more...