AT&T
Dial (800) 225-5288 (CALL-ATT) and follow the instructions (for calling card, credit card, or customer service).
MCI
Dial (800) 674-7000. (World Phone card customers should dial (800) 888 8000 ) Enter MCI card number and then the party's area code and phone number.
For international calls, dial (800) 674-7000. Enter MCI card number, then 011, and then the party's country code and number.
Sprint
Dial 1-0-333-0 and then the party's area code and number. You should hear "Welcome to Sprint." Then enter Sprint card number. If not, dial (800) 877 8000. At the tone, dial O and then the party's area code and number. Then enter Sprint card number.
For international calls, dial 1-0-333-0-1 and then the party's country code and number. Then press the # button. If there is a problem, dial (800) 877-8000 and repeat.
To make another call, do not hang up. Hold down the # key for two seconds. At the tone, dial 0 and then the party's area code and number This applies to both domestic and international calls.
Reference Sources
AT&T Toll-Free 800 Directory AT&T, business edition $24.99, consumer edition $14.99, both $34.95 (800) 426-8686.
These are essential references for businesses and consumers. The business edition is a business-to-business directory, with over 150,000 numbers. The consumer edition lets the average person comparison-shop from coast to coast. It contains over 120,000 numbers. Listings are alphabetical by company name in the white pages, and by classified headings in the yellow pages.