Check out the companies making headlines after the bell:

Shares of Stitch Fix surged more than 20 percent in extended trading Monday following the release of the personal styling company's better-than-expected second-quarter earnings and strong full-year outlook. Stitch Fix posted earnings per share of 12 cents on revenues of $370 million. Wall Street expected earnings of 5 cents on revenues of $365 million, according to Refinitiv.

Stitch Fix's active clients increased 18 percent to 2.96 million and beat the estimated 2.95 million.

"Since becoming a public company, we have posted six consecutive quarters of over 20% growth, which demonstrates our ability to drive consistent business performance," said Stitch Fix founder and CEO Katrina Lake in a release.

Stitch Fix issued strong third-quarter and full year guidance.

Coupa Software shares ticked as much as 2 percent lower after hours Monday despite posting better-than-expected fourth-quarter earnings. The technology company reported earnings per share of 5 cents, compared to the 0 cents forecast by analysts. Revenue was $74.9 million, topping estimates of $67.7 million.

Shares of Casey's General Stores fell nearly 2 percent after market close Monday following mixed third-quarter earnings. The convenience store company earned $2.05 billion in revenue, missing Refinitiv estimates of $2.13 billion. Earnings per share were $1.13, compared to the 95 cents analysts forecast. The stock later regained most of its post-market losses to trade slightly negative.

ADT shares dropped as much as 8 percent after hours Monday following fourth-quarter earnings. The security company posted revenue in line with estimates at $1.2 billion. ADT issued light full-year 2019 revenue guidance: between $4.9 and $5.1 billion, compared to the $4.9 billion surveyed by Refinitiv.