Call your local Extension office and ask them when the safe planting dates are for your particular location. It's a good idea to obtain that kind of information regionally.

I bought my cilantro a couple weeks ago when I bought my pansies. It's been outside in a pot on my front steps ever since. It survived the snow Wednesday no problem. In fact I just went out and cut some fresh leaves for guacamole this afternoon. FWIW I'm in MetroWest - pike/128.

I'd keep the rosemary in a bit longer. I don't think rosemary tolerates cold/frost.

Rosemary is a zone 7 perennial. It tolerates frost reasonably well.

Based on the above, I went ahead and planted both on the sunniest/warmest corners of my house. The cilantro seems to already be taking to the spot I've put it in, a nook next to a not-so-well looking golden thyme. Hopefully, the cilantro asserts itself in the bed and fills in the areas where the thyme died back this winter.

We'll see about the rosemary. I'm in 6b/Narragansett Bay area, I'm expecting it to live on into the summer. If it gets frosty enough to kill the rosemary then maybe it's a sign from Earth about something much graver.

Rosemary is not reliably perennial in Zone 7. I lost all my rosemarys this winter - of course the temps were way out of sync for a typical winter here. But even in "normal" winters I've had Rosemary's die. They are meditteranean in origin and like warm temperatures.
My thyme and Sage returned even after this brutal winter.
Lemon balm, which is invasive and grows like a weed, did not survive this winter.
A lot depends on the micro-climate where your plant is.