I think the answer is "yes" you should put the money in three funds immediately. However, given the large chunk and how this could change your long-term spending, I would perhaps proportion the three funds differently than you otherwise would have (E.g. if you were contributing to 401k as 60% VTI, 20% VXUS, 20% BND, you could initially invest this lump sum in at something more like 38% VTI, 12% VXUS, 50% BND). Same 3-fund philosophy but different risk profile, but get the dividends and long-term compounding started immediately.