Hearing Carry-Over, or HCO, is a Maryland Relay service for people who can hear clearly, but have difficulty speaking or being understood over the telephone.
HCO-to-HCO and HCO-to-TTY calling options are also available. To learn more about making and receiving HCO calls, download detailed instructions now, or call 800-552-7724 or 410-767-6960 (Voice/TTY) or 443-453-5970 (Video Phone) to request HCO user training.
HCO users can ask their Maryland Relay Operator for HCO with Privacy when a call begins. With this feature, the Operator is unable to hear the other person’s spoken response to the HCO user.
HCO phones and other assistive telephone devices are available through the Maryland Accessible Telecommunications (MAT) program for qualified Maryland residents. Learn more about the MAT program.
Dial 7-1-1 or 800-735-2258
HCO Calling Instructions
Ameriphone Q90 HCO Phone Instructions
Uniphone HCO Phone Instructions
Create a Customer Profile, a personal profile that automatically lets the Maryland Relay Operator know your communication preferences.
301 W. Preston Street, Suite 1008A Baltimore, MD 21201