Any month is a good time.
Hiring month doesnt really matter if you don't want to be seasonal. If you're interested in applying then go to the website and apply for the top 5 positions you are wanting and qualified for. Then call and ask to speak to HR to let them know you are interested in any of the positions you applied for. They will pull your applications and let them see you are interested in other areas as well. I worked for Walmart for about 2 years closely with the HR department. It's not a bad job as long as it's not a bad store.
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