Aerogramme Studio, a blog dedicated to resources for writers, recently published an extensive list of short story contests for 2018. The list is heavy on established contests and offers with prize money and fellowships for the winners.
Why should you consider submitting your work to a writing contest? To get noticed. Why should you think twice before submitting work to a contest? Because they cost money to enter, your work could be tied up for the duration of the contest and some contests are fake.
One more thing to consider – some contests guarantee one thing. You will gain at least another reader.