The series is based on the comic book series by Beau Smith and was developed for television by Emily Andras.

After the series was renewed for a second season, lead actress Melanie Scrofano found out she was pregnant, and showrunner Emily Andras decided to incorporate the pregnancy into Wynonna's storyline, prompting Syfy to expand the season from 10 to 12 episodes.

Season 1 was filmed from September 2015 to February 2016 in Calgary, Alberta, with locations including Bridgeland, Inglewood, and Heritage Park, while the nearby town of Didsbury stood in for the fictional town of Purgatory.

Production on Season 4 was temporarily suspended on March 16, 2020 after Alberta issued a provincial order halting all television and film productions due to the COVID-19 pandemic; filming resumed later that year to complete the remaining episodes.

Season 4 was delayed for months due to financial difficulties at production company IDW Entertainment, with production only resuming after Cineflix Studios came on board as co-producer and Canada's Crave network joined as a new production partner.

The show's theme song, 'Tell That Devil,' was written and performed by singer-songwriter Jill Andrews, and all episode titles throughout the series are based on country-and-western songs.

Showrunner Emily Andras made an early promise that the show's queer characters would survive, deliberately subverting the 'Bury Your Gays' trope common on television at the time, as shown when Nicole Haught survives being shot in the Season 1 finale because she was wearing a bulletproof vest.

When Season 4 was threatened by IDW Entertainment's financial troubles, devoted fans known as 'Earpers' launched a social media campaign to save the show, including paying for electronic billboards in Times Square, and Melanie Scrofano later sponsored a billboard thanking fans for their support.