Slack posted earnings of 8 cents a share on revenue of $273 million.
The company had been expected to break even on sales of $267.1 million, based on a FactSet survey of 9 analysts. In the same period a year ago the company posted a loss of 2 cents a share on sales of $201.7 million.
Slack reported paid accounts totaling 169,000. It had been expected to report just under 156,000.
"In Q1 we saw a near-record number of Paid Customer additions, a record number of Paid Customers adopting Slack Connect, and approached 1 million active developers on our platform," said Stewart Butterfield, CEO and co-founder at Slack in a statement.
The company said it added 13,000 net new paid customers including 102 net new paid customers spending greater than $100,000 annually,
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Shares of Slack rose 26 cents, or 0.6%, to $43.90 in after-hours trading Thursday. In the regular session the stock fell 0.1%.
The stock has risen 9.4% since the company last reported earnings on March 4.
Salesforce shares fell 1.6% in regular-session trading. They edged higher in after-hours trading.