I am throughly confused with this senario. Looking to you ACH pro's to help me out.
X Bank has a mortgage correspondent who services their loans. Mortgage correspondent bills X Banks customers, X banks customers send their payments to the mortgage correspondent, and the mortgage correspondent ACHs the payments to X bank.
ODFI for the Mortgage Correspondent, P Bank, wants X Bank to sign an ACH agreement with them. I think X bank needs to sign a third party sender agreement with mortgage correspondent.
the way I see it is P Bank is the ODFI, Mortgage correspondent is Third Party Sender & X bank is originator. Am I way off??

P Bank is the ODFI, their customer for ACH purposes is Mortgage Correspondent (MC), there should be agreements in place between the 2 concerning origination.

I'm a little unclear when you say MC ACHs the payments to X Bank. Who is listed as the Originator on the paymetn, the MC or X Bank? Is MC creating the file on behalf of X Bank with X Bank as the originator? Or is MC the originator and when credits are received, they settle with X Bank? Depending how you answer that determines if a 3rd party agreement is needed.

Of course, if P Bank is the ODFI and they want an agreement on file, they can discontinue the service until one is signed, so that is likely all a moot point.

X bank is listed as the originator - MC is creating the file on behalf or X Bank. I believe X Bank needss to sign a TPS agreement with MC, but P bank want's X bank to sign an ACH agreement with them.

If X Bank is the Originator and P Bank is the ODFI, they need an agreement with P Bank, regardless of who is creating the file.

Thanks for your help Happy!