Some places do ask up front for deductibles, co insurances and copays. Basically a lot of doctors got tired of never getting paid. If BM or SD have a history of not paying medical bills it is entirely possible they got asked to pay their portion up front.

Now let me explain how billing works.
Most doctors offices bill out at 200% of the amount Medicare allows for services. Most insurance contracts are written based off what Medicare allows. The doctors contract with the insurance company could be 100% of medicare allowable up to 125% of medicare allowable (rarely will an insurance contract for more than that).

So that 425.00 that is pending, will likely turn into $225.00 allowed. If the services were preauthorized... the insurance company will pay it at 100% (based off your saying they pay 100%). IF SD went to an in network physician/ Xray center.

If she went out of network, the insurance may charge a deductible for out of network (oon) providers. That may be where the $350.00 is coming from... however, if they are only "allow" $225.00 based on contract, she wont be charged the full $350.00 ... she would be charged the $225.00 as the amount allowed would be put towards that OON deductible.

Your best bet:
a) Call the insurance company find out what her patient responsibility is.
b) wait for the EOB to come in and pay the provider directly (If your feeling nice, the kid is 21 and should be responsible for her own bills)

If BM/SD went out of network... I myself would not pay a dime. I can assure you the provider would have told them "we are not in network with your insurance" and explained why they owed the $$ out of pocket. If they chose to have it done there, instead of finding and in network provider that would be paid @ 100%- they are idiots and you should not have to pay for their stupidity.

Eh I forgot to mention: If the provider bills 450.00 and your insurance allows 225.00 the difference between billed and allowed is written OFF by the provider. They do not bill the patient for the difference, they can't due to being contracted with the insurance company.

Even if they are not contracted, and are an out of network provider, there is a "Usual and Customary" fee schedule the insurance companies work off of for OON providers: the provider billing the insurance company is an agreement they will access the Ususal and customary fee schedule and not hold the patient liable for the difference between U&C and billable rates.

Your SD is an ADULT now!! Why is BM still contacting you for an Adult? Put the whole thing on Ignore is what I would do!!! This is no longer between BM & you guys!! BM needs to realize those days are looooooong gone!!!!! IF SD wants your DHs involvement she needs to contact your DH directly!! But,personally if it were my SSs, Id not pay a dime!! I was very much on my own at that age, paying my own bills & all. I was an Adult & never ever thought of asking my parents to pay for MY responsibilites!!! There comes a point where one has to accept responsibility for themselves!!!!

Plus, I personally think BM may be trying to drum up some free money for herself or SD!!! Ive just recently been at my reg Drs office & my spine specialist and neither had any signs up for 'Obamacare' or changed how they accepted Insurance or payments. Perhaps some Drs in some areas of the Country are, but that hasnt happened to me personally yet. An EOB is Not a bill!!! Never go off an EOB to determine how much is or isnt due to the Provider (BM tried that BS tactic with us too-- if we had gone off the EOB we coulda paid $129 to the Dr, however the real amt due to the Dr was our $20 copay & nothing more!!! Thats why every EOB states clearly on it "This is not a bill")!!!

If your DH WANTS to help his Adult Daughter out (which he clearly does NOT have to- shes an Adult!!) he would need to contact his Daughter, not BM!!, and ask for the actual Drs Bill!!! Then, call the Dr to see how much was actually paid or ask SD for her receipt & go from there!!!!

IF BM ever contacts you guys again, I think a simple "this is between SD & DH, NOT you! Please have SD contact us Directly" should be adviseable!! Then tell her to butt out anytime she tries again!! She is just trying to sponge $$ out of you guys, except that ship has long sailed now that SD is an Adult!!! Time to help SD mature & be responsible for herself !

Tell BM to go fly a kite.

I agree with the above posters. This is not a child that DH is responsible for. IF there is an issue the SD should discuss it with him and it is his OPTION on whether to get involved or not.

DH does not EVER EVER EVER have to talk to BM again about anything.