Whenever I have brought any basil inside as a houseplant, it does quite well for 2-3 months, then dies. But, hey, at least I get another several weeks out of it.

Agreed.

The only basil I've successfully overwintered is holy basil. But that is a perennial and a different type of plant altogether.

FataMorgana

I've overwintered sweet basil in a windowsill that only got about 5 hours of overcast sunlight a day. It wasn't looking that great by the end of winter but it came back around once I put it outside again in the spring. However, I'm not sure how sweet basil would compare to your Thai basil.

Thanks one and all. I will try a small portion of the plant inside to see how it goes. It has done quite well outside this summer in partial shade.

DL

DL, I tried keeping sweet basil and chives indoors during winter a couple of years ago. I kept them near a sunny window and I provided bottom heat. The chives were happier than the basil which got a little leggy. I think if I had provided some additional artificial lighting, the basil would have been much happier. You may know this already, but thought it worth mentioning to keep the basil away from heater vents, and a good distance from windows which radiate cold.

Are you ready for a 4-5 foot tall indoor plant? Artifical lighting would need to be on about 20 hours per day.

Just beginning my testing of Thai basil but, I do have experience with sweet basil as a houseplant. Sweet basil does best in a west facing window and as long as you cut it back so it bushes no problem at all. It is coming along fairly well in my new apt. with its southern exposure with a large overhang. It gets very leggy just sitting inside but the one I set out each day for a few hours of mid day sun is performing well. In winter, this window gets a lot of direct sun so I am expecting no problems at all. The Thai basil uses amazing amounts of water here in New Mexico's dry climate, I actually have placed the pot in a clear container just a bit larger than the pot and add water up to the level of the soil every day.Otherwise, it seems to be acting just like the sweet basil. Both require regular pruning so that they do not get leggy but since I cook with them both I don't mind. One thing though, Thai basil does not keep flavor when dried anywhere near as well as the sweet basil. Hope someone finds this useful.

Just wondering why artificial light wouldn't be a something you just assume you'd need to do? Unless you live in Arizona, I wouldn't imagine the window would be enough for overwintering any summertime herb.