I've used TriNet and Namely. Granted, even at the companies I founded, I was not the one to choose the specific package of benefits we decided to offer, and nei

I've used TriNet and Namely. Granted, even at the companies I founded, I was not the one to choose the specific package of benefits we decided to offer, and neither of those companies offered a 401k at all (though I've since had 401ks through both of the above PEOs). The timing of when 401k benefits kicks in is the least of ones concerns in terms of developing a company culture, IMO. Edited to add: I do know that some of the companies I was at had benefits begin immediately; others had a one to three month delay.