They won't do anything but take your information at the hospital. They'll bill it to the insurance and then bill you for whatever your part is later. The ER doesn't expect payment at the time of service. I didn't have to pay my ER co-pay until later any of the 4 times I've been to the ER for different things and a lot of the time if you are admitted you won't have an ER co-pay, just your regular hospitalization co-pay/deductible.