Affordable portrait lens for my 6d

Canon 70-200 f4L

Another vote for the 100mm f2. I liked it better than the 85mm 1.8. Less CA and better bokeh. As a second choice, I'd choose the 100mm 2.8 macro. The only lens in this general focal range better than the 100mm f2 as a portrait lens is the 135mm f2 and that's out of your price range.

Well I'm not gonna lie, I came here asking for advice but went with my initial feelings and bought a 50 1.4 at the bargain price of $300 nzd, it is used but near new, I do actually have a 70-200 2.8 which already has me covered for that focal length although it is not as fast as some of the portrait lenses suggested.
when I asked for portrait lens advice I probably lead you all astray a little I want a lens that can take great shallow dof pics of friends & family etc but not necessarily in true portrait style, I'll also use it for event photography/sports so hopefully it will fulfill my needs

Thanks guys

I had the 70 2.8 sigma macro, 100 f2 canon, and have the 135f2. for the price the sigma was pretty amazing, was sharper than the 135 f2, had close to the same colors. didn't have quite the dof due to focal length and fstop though.

35 f2 IS