BoatUS, itself, does not accept float plans - some of the independent towing companies do. That, in my opinion, is far too much liability for any private company to accept. The first time someone gets sued for not contacting the CG when a boat is overdue is when you'll see everyone refuse to accept them. The CG won't accept them just for that reason. You need to leave a float plan with someone you know will respect the commitment required.