Is it inside our outside? Some Coleus are bigger than others, and 'Chocolate Mint' is one of the big ones. The pot does not sound big enough for it to stay for that amount of time. If you are nervous about repotting, you could root some cuttings first, as insurance.

Coleus are sold here as summer annuals (although many will winter them over indoors) and as such, get repotted frequently and at all times of the season. I would have absolutely no concern about planting directly into the garden now or up-potting if you prefer to keep in a container!

Excellent point. That is probably true for all but the very warmest, frost-free spots in the US, where a Coleus could really survive perennially.

I have it strictly as a house plant. I'll go ahead and repot it into an 8 inch pot now. I'll take a couple of cuttings just in case. Thank you for the advice!