Maryland Department of Corrections

Telephone calls made from the housing units are collect calls only. The call can be made through Verizon or else Correctional Billing Services may be contyacted to set up an account to receive collect calls. The telephone number to CBS is: -1-800-844- 6591 or their website at www.correctionalbillingservices.com may be visited  for more information.

There is an allotted time limit per phone call, and the telephone system will notify inmates when they have one minute remaining and will automatically shut off after the time limit has elapsed. To avoid being disconnected, don't
• Transfer the call
• Put the call on Hold
• Use or answer Call Waiting
• Try to make any 3-way calls

Pre-paid

Pre-paid plan has no restrictions as long as funds are available in account. To sign up for the pre-paid plan a minimum payment of $25.00 is needed. The transaction fees may apply. The following payment methods can be used: 

1. Visa             
2. Master Card  
3. Checking account

The automated system can notify you and let you know when you need to make additional payments to prevent any restrictions from receiving calls. Payments can be made through our IVR, through CBS website and even by sending  check by  mail CBS billing office at:
PO Box 650757
Dallas, TX 75265-0757

Western Union

The  payments can also be made to pre-paid and direct bill payments options through Western Union. Payments can easily be made online through a Western Union® Quick Collect® payment.

Local Telephone Payments

CBS have billing arrangements with some local phone companies. With this option, one has a 90 day spending limit and are subject to more rigorous controls. Payments must be made to  local telephone company. Each customer is assigned with a 90 day rolling spending limit, which is the credit limit assigned to CBS account that is billed through local phone company. Each time a call is accepted, the charges are deducted from available spending limit. The spending limit works on a 90 day rolling basis. As the first billed call reaches the 91st day, it will deduct from the total amount billed. If one reaches or exceed spending limit, the other options are available. The account may be switched  to prepaid, direct bill, or depending on local carrier, one may be able to make an advance payment directly to CBS for unbilled calls. If spending limit is reached, the account will be blocked from accepting additional calls. 

Bill Statement Fee: A monthly Bill Statement Fee of up to $2.49 may be applied to local telephone bill if calls from correctional facilities are billed through your local telephone company. This fee will be charged in addition to the costs of individual calls as well as any government taxes or fees.
This fee can be avoided by establishing a prepaid account with Correctional Billing Services (CBS), ll. With a pre-paid plan, one may establish an account for a minimum payment of $25.00, which prevents line from being restricted as long as there are available funds in  account. CBS automated system can notify when an additional payment is needed to prevent line from being restricted.

http://www.dpscs.state.md.us/locations/pdfs/InmateTelephonePrivileges.pdf
https://www.correctionalbillingservices.com/general/Payonline.aspx