Flash Frontier is a New Zealand based flash fiction challenge and competition site. They invite fellow New Zealanders and Kiwi’s abroad to join them. I don’t know if this means others cannot participate.
They publish bi-monthly based on themes. Submissions are accepted until the last day of the month for the next months theme.
Flash Frontier is looking for flash fiction, 250 words or less. 251 will not be accepted.
They have explicit instructions on how to submit through email.
Flash Frontier does not pay for publication, but there are prizes awarded.