Charlotte Douglas International Airport, in Charlotte, United States.

What is the difference between CLT and KCLT?

CLT is the IATA code, used commercially — tickets, timetables, luggage tags. KCLT is the ICAO code, used operationally by pilots and air traffic control, and assigned geographically by region.

Is CLT the same as CHA?

No. CHA is chattanooga, Tennessee. The code Charlotte could not have.

What airport is CLT?

CLT is

Charlotte Douglas International Airport

Charlotte, United States

Why the code is CLT

CharLoTte, using the consonants because CHA was already taken by Chattanooga.

This is the explanation in general circulation and it is very likely right, but no primary document has been published that settles it. Treated as an account rather than a fact.

The airport

IATA code: CLT
ICAO code: KCLT
Airport: Charlotte Douglas International Airport
City: Charlotte, United States
Code origin: The usual account, unverified

Charlotte is one of the busiest airports in the world by aircraft movements while being nowhere near the busiest by passengers, because it is a connecting hub built on regional jets — many flights, few seats each. The terminal is known for its rocking chairs, of which there are several hundred.

Codes people book by mistake

Code	What it actually is
CHA	Chattanooga, Tennessee. The code Charlotte could not have.

The other code, KCLT

Every airport has two codes. The three-letter IATA code, CLT, is the one on your boarding pass and your luggage tag, and it is assigned for commercial use. The four-letter ICAO code, KCLT, is the one pilots and controllers use, and it is assigned geographically: the first letter or two identify the region, so every airport in the same part of the world shares a prefix. That is why KCLT looks nothing like CLT.

Common questions

What airport is CLT?: Charlotte Douglas International Airport, in Charlotte, United States.
Why is Charlotte's airport called CLT?: CharLoTte, using the consonants because CHA was already taken by Chattanooga.
What is the difference between CLT and KCLT?: CLT is the IATA code, used commercially — tickets, timetables, luggage tags. KCLT is the ICAO code, used operationally by pilots and air traffic control, and assigned geographically by region.
Is CLT the same as CHA?: No. CHA is chattanooga, Tennessee. The code Charlotte could not have.

United States Capital, area, population and currency
The flag of United States Colours, symbols and lookalikes
Airport codes in United States 32 here
What airport is JFK? John F. Kennedy International Airport, New York
What airport is LAX? Los Angeles International Airport, Los Angeles
What airport is ORD? O'Hare International Airport, Chicago
What airport is ATL? Hartsfield-Jackson Atlanta International Airport, Atlanta
What airport is MCO? Orlando International Airport, Orlando
What airport is DFW? Dallas/Fort Worth International Airport, Dallas
What airport is EWR? Newark Liberty International Airport, Newark
What airport is SFO? San Francisco International Airport, San Francisco

Sources

OurAirports — OurAirports (Public domain)

How these figures are compiled and checked