Nubank posts 87% increase in fourth-quarter adjusted profit

Adds share move in paragraph 3, details of the report in paragraphs 4-6

By Andre Romani

SAO PAULO, Feb 20 (Reuters) - Brazilian digital lender Nubank NU.N posted on Thursday an 87% increase in its fourth-quarter adjusted net profit from a year earlier.

Nubank, which is listed on the New York Stock Exchange through Nu Holdings NU.N, reported an adjusted net profit of $610 million for the quarter ended in December, above the $567 million estimated by analysts in an LSEG poll.

Still, shares of Nu Holdings were down some 6% in after-hours trading follwing the publication of the quarterly report.

The Warren Buffett-backed firm posted revenues rising 50%, excluding foreign-exchange effects, to $2.99 billion, below analysts' estimate of $3.29 billion. Its annualized adjusted return on equity, a gauge of profitability, stood at 32%, from 26% a year earlier.

One of the largest and most successful digital lenders in the world, with more than 114 million customers across operations in Brazil, Colombia and Mexico, Nubank's credit portfolio increased some 45% year-on-year to $20.7 billion, although it ticked down from the $20.9 billion posted in the previous quarter.

The 90-day-plus default ratio for loans in Brazil, its largest client base, came in at 7%, down 0.2 percentage points from last quarter, but up from 6.1% a year earlier.