Phonetic Alphabet for IT Support
The definitive guide to spelling serial numbers, MAC addresses, passwords, and license keys clearly over the phone — without costly errors.
Why IT Support Needs Phonetic Spelling
A single wrong character in a serial number, license key, or MAC address can mean hours of wasted troubleshooting. IT support handles the most error-prone communication of any industry: random alphanumeric strings with mixed case, where zero looks like O, one looks like lowercase L, and five looks like S in certain fonts. The NATO phonetic alphabet eliminates this ambiguity entirely.
The Dangerous Pairs
0 / O
Zero vs Oscar
1 / l / I
One vs Lima vs India
5 / S
Five vs Sierra
2 / Z
Two vs Zulu
B / 8
Bravo vs Eight
G / 6
Golf vs Six
Real-World Scenarios
Serial Numbers & License Keys
SN: X4K-9BF-2MP
X-ray Four Kilo — Niner Bravo Foxtrot — Two Mike Papa
Pro tip: Always clarify dashes: say "dash" not "minus" or "hyphen." Spell each group separately with a pause between groups.
MAC Addresses
MAC: 5E:A3:F1:0B:72:D9
Five Echo — Alfa Three — Foxtrot One — Zero Bravo — Seven Two — Delta Niner
Pro tip: For hex digits, clarify that letters are part of the address: "Foxtrot as in the letter F, not the number."
IP Addresses
IP: 192.168.1.105
One Niner Two — dot — One Six Eight — dot — One — dot — One Zero Five
Pro tip: Say "dot" between octets, never "point" or "period." Read each number group as individual digits for clarity.
Passwords (case-sensitive)
Pass: Tr0ub4dor
CAPITAL Tango, lowercase Romeo, ZERO (not the letter O), lowercase Uniform, lowercase Bravo, the number FOUR (not the letter A), lowercase Delta, lowercase Oscar, lowercase Romeo
Pro tip: Always specify "capital" or "lowercase" for every letter. Distinguish zero from O and one from lowercase L explicitly.
Email Addresses
j.smith_2@company.co.uk
Juliett dot Sierra Mike India Tango Hotel underscore Two at Charlie Oscar Mike Papa Alfa November Yankee dot Charlie Oscar dot Uniform Kilo
Pro tip: Spell out every special character: "dot", "underscore", "at sign", "dash." Never assume the listener knows the domain format.