Indoor seed starting for basil in zone 8

[River]

I know they like heat, and we usually average last frost March 15th or a week or so later.
I want to know when u would start.

i would like to make several plantings

[rainbowgardener]

Depends on the basil. I find the purple basils to be considerably slower than the green. So I start purple basil early in February and green basil a couple weeks later. It doesn't take the green basil very long to catch up.

I agree with Marlin-g. Why would you do succession plantings of basil? You do that for things like lettuce that bolt and are done quickly. Basil, if you just keep cutting it back so it doesn't flower, will go on all season and you can just keep cutting from it.

[River]

The reason for several plantings is they can Peter out so keep a fresh supply

[Gardener_Wes]

You should be fine starting inside. You can actually grow basil inside if you have good enough window light.

[Susan W]

Basil starts well just with regular house temps, I have found (60's night, 70's day) My thermostat is below 70, but one area for seeds is warmer with lights and near heat register They take up to 5 days, with heat mat 3,
As for setting out, basil doesn't like below 40, and just never seems to recover if out too early in spring. I would plan for 6 wks to planting for small plants, 8 wks for bigger. Of course you can put the plantlets out to harden especially during the day in sheltered spot before planting.

I like some fresh ones coming along also. Hopefully you will not get the dreaded downy mildew.