This is a list of broadcast station classes applicable in much of North America under international agreements between the United States, Canada and Mexico. Effective radiated power (ERP) and height above average terrain (HAAT) are listed unless otherwise noted.

All radio and television stations within 320 kilometers (about 200 miles) of the U.S.-Canada or U.S.-Mexico border must get approval by both the domestic and foreign agency. These are Industry Canada/Canadian Radio-television and Telecommunications Commission (CRTC) in Canada, the Federal Communications Commission (FCC) in the U.S., and the Secretaría de Comunicaciones y Transportes (SCT) in Mexico.

AM

• A (former I): clear-channel stations, 10 kW to 50 kW day and night
• B (former II and III): 250 W to 50 kW (to 10 kW on 1620 kHz to 1710 kHz)
  • D (former II-D, II-S, III-S): daytime 250 W to 50 kW, nighttime under 250 W or off-air, field strength up to 140 mV/m at 1 km, no new stations except downgraded B
• C (former IV): 250 W to 1 kW (also grandfathered 100 W)
• TIS/HAR: travelers' information stations up to 10 W transmitter output power, licensed by NTIA (not FCC) in U.S. national parks
• Unlicensed broadcasting (see low-power broadcasting): 100 mW, no license needed (US only? ), may be measured at edge of campus for school stations

Notes

• In the Western Hemisphere (ITU region 2), medium wave AM broadcasts are on channels spaced 10 kHz apart from 530 kHz to 1700 kHz, with certain classes restricted to subsets of the available frequencies.
• Class A stations can be found only on the frequencies of 540 kHz, 640 to 780 kHz, 800 to 900 kHz, 940 kHz, 990 to 1140 kHz, 1160 to 1220 kHz, and 1500 to 1580 kHz.
• While Class A stations can only operate at a maximum of 50,000 watts day and night, from 1934 to 1939, Cincinnati's class A station 700 WLW broadcast at 500,000 watts under an experimental license. The signal was able to cover the entire continent and reach overseas, but was soon shut down due to complaints from competitors and stations in far away cities where the 700 kHz frequency was bleeding into nearby stations on the dial.
• Class B and D stations can be found on any frequencies from 540 kHz to 1700 kHz except where frequencies have been reserved for Class C stations.
• Class C stations can be found in the lower 48 US states on the frequencies of 1230 kHz, 1240 kHz, 1340 kHz, 1400 kHz, 1450 kHz, and 1490 kHz. Other countries may use other frequencies for their Class C stations.
• TIS stations can be found on any frequency from 530 kHz to 1700 kHz in the US, but may only carry non-commercial messages without music.
• Low-power AM stations located on a school campus are allowed to be more powerful, so long as their signal strength does not exceed roughly 14 to 45 µV/m² (depending on frequency) at a distance of 30 meters (98.4 ft) from campus.
• AM classes were previously assigned Roman numerals from I to IV in the US, with subclasses indicated by a letter suffix. Current class A is equivalent to the old class I; class B is the old classes II and III, with class D being the II-D, II-S, and III-S subclasses; and class C is the old class IV.
  • The following conversion table compares the old AM station classes with the new AM station classes:

Old Domestic Class	New Domestic Class
I	A
II	B
III	B
IV	C
II-S	D
III-S	D
II-D (Daytime Only)	D

AM Classes and Clear Channels

• The following chart is a list of available classes and Clear Channel Station listings in the United States.

Channel Type	Frequency (kHz)	Available Classes	Assignment Old class designation in ()
----	530	----	In the USA, reserved for low power AM Travelers' Information Stations
Clear	540	A,B,D	Canadian/Mexican Clear
Regional	550	B,D	All Stations
Regional	560	B,D	All Stations
Regional	570	B,D	All Stations
Regional	580	B,D	All Stations
Regional	590	B,D	All Stations
Regional	600	B,D	All Stations
Regional	610	B,D	All Stations
Regional	620	B,D	All Stations
Regional	630	B,D	All Stations
Clear	640	A,B,D	KFI Los Angeles, CA: Class A (I-A) KYUK Bethel, AK: Class A (I-N)
Clear	650	A,B,D	WSM Nashville, TN: Class A (I-A) KENI Anchorage, AK: Class A (I-N)
Clear	660	A,B,D	WFAN New York, NY: Class A (I-A) KFAR Fairbanks, AK: Class A (I-N)
Clear	670	A,B,D	WSCR Chicago, IL: Class A (I-A) KDLG Dillingham, AK: Class A (I-N) KBOI Boise, ID: Class B (II-A)
Clear	680	A,B,D	KNBR San Francisco, CA: Class A (I-B) KBRW Barrow, AK: Class A (I-N)
Clear	690	A,B,D	Canadian/Mexican Clear
Clear	700	A,B,D	WLW Cincinnati, OH: Class A (I-A) KBYR Anchorage, AK: Class A (I-N)
Clear	710	A,B,D	WOR New York, NY: Class A (I-B) KIRO Seattle, WA: Class A (I-B)
Clear	720	A,B,D	WGN Chicago, IL: Class A (I-A) KOTZ Kotzebue, AK: Class A (I-N) KDWN Las Vegas, NV: Class B (II-A)
Clear	730	A,B,D	Canadian/Mexican Clear
Clear	740	A,B,D	Canadian Clear
Clear	750	A,B,D	WSB Atlanta, GA: Class A (I-A) KFQD Anchorage, AK: Class A (I-N)
Clear	760	A,B,D	WJR Detroit, MI: Class A (I-A)
Clear	770	A,B,D	WABC New York, NY: Class A (I-A) KKOB Albuquerque, NM: Class B (II-A) KCHU Valdez, AK: Class A (I-N)
Clear	780	A,B,D	WBBM Chicago, IL: Class A (I-A) KNOM Nome, AK: Class A (I-N) KKOH Reno, NV: Class B (II-A)
Regional	790	B,D	All Stations
Clear	800	A,B,D	Mexican Clear
Clear	810	A,B,D	KGO San Francisco, CA: Class A (I-B) WGY Schenectady, NY: Class A (I-B)
Clear	820	A,B,D	WBAP Fort Worth, TX: Class A (I-A) KCBF Fairbanks, AK: Class A (I-N)
Clear	830	A,B,D	WCCO Minneapolis, MN: Class A (I-A)
Clear	840	A,B,D	WHAS Louisville, KY: Class A (I-A)
Clear	850	A,B,D	KOA Denver, CO: Class A (I-B) KICY Nome, AK: Class A (I-N)
Clear	860	A,B,D	Canadian Clear
Clear	870	A,B,D	WWL New Orleans, LA: Class A (I-A) KSKO McGrath, AK: Class A (I-N)
Clear	880	A,B,D	WCBS New York, NY: Class A (I-A) KRVN Lexington, NE: Class B (II-A)
Clear	890	A,B,D	WLS Chicago, IL: Class A (I-A) KBBI Homer, AK: Class A (I-N) KDXU St. George, UT: Class B (II-A)
Clear	900	A,B,D	Mexican Clear
Regional	910	B,D	All Stations
Regional	920	B,D	All Stations
Regional	930	B,D	All Stations
Clear	940	A,B,D	Canadian/Mexican Clear
Regional	950	B,D	All Stations
Regional	960	B,D	All Stations
Regional	970	B,D	All Stations
Regional	980	B,D	All Stations
Clear	990	A,B,D	Canadian Clear
Clear	1000	A,B,D	WMVP Chicago, IL: Class A (I-A) KOMO Seattle, WA: Class A (I-B)
Clear	1010	A,B,D	Canadian Clear
Clear	1020	A,B,D	KDKA Pittsburgh, PA: Class A (I-A) KCKN Roswell, NM: Class B (II-A) KAXX Eagle River, AK: Class A (I-N)
Clear	1030	A,B,D	WBZ Boston, MA: Class A (I-A) KTWO Casper, WY: Class B (II-A)
Clear	1040	A,B,D	WHO Des Moines, IA: Class A (I-A)
Clear	1050	A,B,D	Mexican Clear
Clear	1060	A,B,D	KYW Philadelphia, PA: Class A (I-B)
Clear	1070	A,B,D	KNX Los Angeles, CA: Class A (I-B)
Clear	1080	A,B,D	WTIC Hartford, CT: Class A (I-B) KRLD Dallas, TX: Class A (I-B) KUDO Anchorage, AK: Class A (I-N)
Clear	1090	A,B,D	KAAY Little Rock, AR: Class A (I-B) WBAL Baltimore, MD: Class A (I-B)
Clear	1100	A,B,D	WTAM Cleveland, OH: Class A (I-A) KNZZ Grand Junction, CO: Class B (II-A)
Clear	1110	A,B,D	WBT Charlotte, NC: Class A (I-B) KFAB Omaha, NE: Class A (I-B)
Clear	1120	A,B,D	KMOX St. Louis, MO: Class A (I-A) KPNW Eugene, OR: Class B (II-A)
Clear	1130	A,B,D	KWKH Shreveport, LA: Class A (I-B) WBBR New York, NY: Class A (I-B)
Clear	1140	A,B,D	WRVA Richmond, VA: Class A (I-B)
Regional	1150	B,D	All Stations
Clear	1160	A,B,D	KSL Salt Lake City, UT: Class A (I-A)
Clear	1170	A,B,D	KFAQ Tulsa, OK: Class A (I-B) WWVA Wheeling, WV: Class A (I-B) KJNP North Pole, AK: Class A (I-N)
Clear	1180	A,B,D	WHAM Rochester, NY: Class A (I-A) KOFI Kalispell, MT: Class B (II-A)
Clear	1190	A,B,D	KEX Portland, OR: Class A (I-B)
Clear	1200	A,B,D	WOAI San Antonio, TX: Class A (I-A)
Clear	1210	A,B,D	WPHT Philadelphia, PA: Class A (I-A) KGYN Guymon, OK: Class B (II-A)
Clear	1220	A,B,D	Mexican Clear
Regional	1230	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1230	C	Stations in coterminous 48 states
Regional	1240	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1240	C	Stations in coterminous 48 states
Regional	1250	B,D	All Stations
Regional	1260	B,D	All Stations
Regional	1270	B,D	All Stations
Regional	1280	B,D	All Stations
Regional	1290	B,D	All Stations
Regional	1300	B,D	All Stations
Regional	1310	B,D	All Stations
Regional	1320	B,D	All Stations
Regional	1330	B,D	All Stations
Regional	1340	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1340	C	Stations in coterminous 48 states
Regional	1350	B,D	All Stations
Regional	1360	B,D	All Stations
Regional	1370	B,D	All Stations
Regional	1380	B,D	All Stations
Regional	1390	B,D	All Stations
Regional	1400	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1400	C	Stations in coterminous 48 states
Regional	1410	B,D	All Stations
Regional	1420	B,D	All Stations
Regional	1430	B,D	All Stations
Regional	1440	B,D	All Stations
Regional	1450	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1450	C	Stations in coterminous 48 states
Regional	1460	B,D	All Stations
Regional	1470	B,D	All Stations
Regional	1480	B,D	All Stations
Regional	1490	B	Stations in AK, HI, PR, and the U.S.V.I.
Local	1490	C	Stations in coterminous 48 states
Clear	1500	A,B,D	WFED Washington, D.C.: Class A (I-B) KSTP St. Paul, MN: Class A (I-B)
Clear	1510	A,B,D	WLAC Nashville, TN: Class A (I-B) KGA Spokane, WA: Class A (I-B)
Clear	1520	A,B,D	WWKB Buffalo, NY: Class A (I-B) KOKC Oklahoma City, OK: Class A (I-B)
Clear	1530	A,B,D	KFBK Sacramento, CA: Class A (I-B) WCKY Cincinnati, OH: Class A (I-B)
Clear	1540	A,B,D	KXEL Waterloo, IA: Class A (I-B)
Clear	1550	A,B,D	Canadian/Mexican Clear
Clear	1560	A,B,D	KNZR Bakersfield, CA: Class A (I-B) WQEW New York, NY: Class A (I-B)
Clear	1570	A,B,D	Mexican Clear
Clear	1580	A,B,D	Canadian Clear
Regional	1590	B,D	All Stations
Regional	1600	B,D	All Stations
Regional	1610	B,D	All Stations
Regional	1620	B,D	All Stations
Regional	1630	B,D	All Stations
Regional	1640	B,D	All Stations
Regional	1650	B,D	All Stations
Regional	1660	B,D	All Stations
Regional	1670	B,D	All Stations
Regional	1680	B,D	All Stations
Regional	1690	B,D	All Stations
Regional	1700	B,D	All Stations

For listings of Clear Channel Stations in Canada and Mexico, visit the Clear-channel station page on Wikipedia.

See also: North American Radio Broadcasting Agreement (NARBA)

FM

• C: 100 kW, 300 m to 600 m, 91.8 km
• C0: 100 kW, 300 m to 450 m, 83.4 km
• C1: up to 100 kW, under 300 m, 72.3 km
• C2: up to 50 kW, up to 150 m, 52.2 km
• C3: up to 25 kW, up to 100 m, 39.1 km
• B: up to 50 kW, up to 150 m, 65.1 km
• B1: up to 25 kW, up to 100 m, 44.7 km
• A: 100 W to 6 kW, up to 100 m, 28.3 km
  • AA (Mexico): up to 3 kW, the former limit for A
• D: up to 250 W ERP, except U.S. non-translators to 10 W TPO
  • L1 (U.S., also LP100): 50 W to 100 W ERP, up to 30 m, 5.6 km
  • L2 (U.S., also LP10): 1W to 10 W ERP, up to 30 m, 3.2 km
• Unlicensed: 250µV/m at 3m in U.S., 100µV/m at 30m in Canada

Notes:

• Canada protects all radio stations out to a signal strength of 0.5mV/m (54dBu), whereas only commercial B stations in the U.S. are. Commercial B1 in the U.S. is 0.7mV/m (57dBu), and all other stations are 1.0mV/m (60dBu). Noncommercial-band stations (88.1 to 91.9) are not afforded this protection, and are treated as C3 and C2 even when they are B1 or B. C3 and C2 may also be reported internationally as B1 and B, respectively.
• Class C0 is for former C stations, demoted at request of another station which needs the downgrade to accommodate its own facilities.
• In practice, many stations are above the maximum HAAT for a particular class, and correspondingly must downgrade their power to remain below the reference distance. Conversely, they may not increase power if they are below maximum HAAT.
• All class D (including L1 and L2 LPFM and translator) stations are secondary in the U.S., and can be bumped or forced off-air completely, even if they are not just a repeater and are the only station a licensee has.
• The United States is divided into separate regions that have different restrictions for FM stations. Zone I (much of the U.S. Northeast and Midwest) and I-A (most of California, plus Puerto Rico) is limited to classes B and B1, while Zone II (everything else) has only the C classes. All areas have the same classes for A and D.
• Power and height restrictions were put in place in 1962. A number of previously-existing stations were grandfathered in, such as KRUZ in Santa Barbara, California and WMC-FM in Memphis, Tennessee.

FM classes

• The following table lists the various classes of FM stations, the reference facilities for each station class, and the protected and city grade contours for each station class:

FM Station Class	Reference (maximum) facilities for station class (ERP / HAAT)	FM protected or primary service contour	Distance to protected or primary service contour	Distance to 70 dBu city-grade or principal community coverage contour
Class A	6 kW	60 dBu (1.0mV/m)
Class B1	25 kW	57 dBu (0.7mV/m)
Class B	50 kW	54 dBu (0.5mV/m)
Class C3	25 kW	60 dBu (1.0mV/m)
Class C2	50 kW	60 dBu (1.0mV/m)
Class C1	100 kW	60 dBu (1.0mV/m)
Class C0	100 kW	60 dBu (1.0mV/m)
Class C	100 kW	60 dBu (1.0mV/m)

Historically, there were local "Class A" frequencies (like A.M. radio's class C stations) to which only class A stations would be allocated & the other frequencies could not have a class A. According to the 1982 F.C.C. rules & regulations those frequencies were: 92.1, 92.7, 93.5, 94.3, 95.3, 95.9, 96.7, 97.7, 98.3, 99.3, 100.1, 100.9, 101.7, 102.3, 103.1, 103.9, 104.9, 105.5, 106.3 & 107.1.

FM zones

Zone I in the U.S. includes all of Connecticut, the District of Columbia, Delaware, Illinois, Indiana, Massachusetts, Maryland, New Jersey, Ohio, Pennsylvania, Rhode Island, and West Virginia. It also includes the areas south of latitude 43.5°N in Michigan, New Hampshire, New York, and Vermont; as well as coastal Maine, southeastern Wisconsin, and northern and eastern Virginia.

Zone I-A includes California south of 40°N, as well as Puerto Rico and the U.S. Virgin Islands.

TV

Full-power stations

• VHF low (2-6): 100 kW video, 10 kW audio; 45 kW digital (sliding scale varying with height)
• VHF high (7-13): 316 kW video, 31.6 kW audio; 160 kW digital (sliding scale varying with height)
• UHF all (14-69): 5 MW video, 500 kW audio; 1MW digital

Notes:

• All Full power analog television station transmissions in the USA were terminated at midnight Eastern Time on June 12, 2009. Many broadcasters will replace their analog signal with their digital ATSC signal on the same transmission channel.
• Power-level limitations are not firmly enforced in Canada, and Industry Canada has been known to license stations for power levels much higher than the generally-accepted limits. For example, CFRN-TV in Edmonton, Alberta operates on Channel 3 at over 600 kW but is not subject to international co-ordination due to its location 500 km north of the border.
• Some U.S. and all Canadian TV stations have the -TV suffix. Some early digital-only television stations in the U.S. have the suffix of -DT (though some early on in the adaptation to digital television had the suffix of -HD, which has since been discontinued).

Class A

Class-A stations (U.S.) (suffix: -CA or -CD for digital class A):

• VHF all (2-13): 3 kW video; 300 W digital
• UHF all (14-69): 150 kW video; 15 kW digital

The class-A television class was created in 2000 by the FCC to allocate and protect some low-power affiliates. Class-A stations are still low-power, but are protected from RF interference and from having to move should a full-service station request that channel. [84010]

Low-power TV

LPTV (secondary) (suffix: -LP, or a sequential-numbered callsign in format W##XX with no suffix for analogue or with -D suffix for digital, or -LD for low-power digital stations):

• VHF all (2-13): 3 kW video; 300 W digital
• UHF all (14-69): 150 kW video; 15 kW digital
• Experimental
• Unlicensed: not allowed except for medical telemetry, and certain wireless microphones

The LPTV (low-power television) service was created in 1982 by the FCC to allocate channels for smaller, local stations, and community channels, such as public access stations. LPTV stations that meet additional requirements such as children's "E/I" core programming and Emergency Alert System broadcasting capabilities can qualify for a Class A (-CA) license. [84011]

Broadcast translators, boosters, and other LPTV stations are secondary, unless they have upgraded to class A. Class A is still considered LPTV with respect to stations in Canada and Mexico.

The United States Federal Communications Commission lists the following services on their website for television broadcasting:

Broadcast class	Service	Suffixes used or call sign examples
TV full-service	TV	-TV, none (such as "WABC-TV" and "WMYD")
Class A	CA	-CA (sometimes uses -LP, or even translator-style call signs)
Low-power station/translator	TX	-LP, none (such as "WLPC-LP" or a translator-style sequential-per-channel identifier like "W66BV")
Television allotment	TA	An allocation of a frequency to a city of licence for which no corresponding call sign or license has been assigned. FCC placeholder for possible future construction permits or frequencies allocated to non-US broadcast use. No callsign, identifier is a date (yymmdd) followed by a sequential two-letter value in the US FCC database.
Low-power TV (LPTV)	TL	Usually placed under TX class; these use -LP or translator-style callsigns.
TV boosters	TB	Rare. These use the parent station's calls plus a sequential number, such as WSTE1, WSTE2, WSTE3. Nameplates for on-channel repeaters bear the parent station's calls, followed by "booster". See distributed transmission.
TV auxiliary (backup) service	TS	none (uses same callsign as main transmitter)
Digital television	DT	-DT, -TV, none (such as KGLA-DT, WSKY-TV or WMAK); some stations formerly used -HD but this has become obsolete. The -DT suffix is used primarily to distinguish a DTV transmission from an analog signal of the same broadcast, and appears as optional for digital-only stations; likewise -TV is optional except if the eponymous radio stations exist.
Digital class-A	DC	-DC/-CD many stations have -CA for analog and -LD for digital
Digital low-power	LD	-LD, translator-style calls or translator-style calls with -D suffix. (though some stations briefly used -DL as well; this has since become obsolete)
Digital special temporary authority (STA)	DS	No change. This is used temporarily with permission from the FCC to use a channel, power level or transmitter location not permanently allocated for one particular station, until another becomes free for use. Temporary assignments retain, unmodified, the callsign of the corresponding permanent allocation; this includes translator-style calls (a format, such as W55ZZ, based on RF channel number plus a sequential identifier) even on temporarily moving to another frequency.
Digital auxiliary (backup) service	DX (not to be confused with DXing)	-DT, same as associated main transmitter
Digital rulemaking petition	DR	(request to add or modify a digital channel allocation)
Land mobile use of a TV channel	LM	As "LM" is used in the FCC database to indicate reallocation of an entire channel, but not to identify individual users transmitting in that spectrum, a 6MHz LM allocation does not itself carry a TV-style callsign.
NTSC (analog) petition for a channel change	NN	Request for a number/channel change (for NTSC/analog stations, and low-power repeaters, such as those registered as TX).

See also

• North American call sign - How call signs and classes are used in North America
• ITU prefix - How callsigns and classes are used worldwide
• Low-power broadcasting
• Class A television service

References

External links

• FCC AM classes
• FCC FM classes
• FCC LPTV Facts
• FCC LPTV classes
• FCC Class-A TV Information
• FCC FM Broadcast Zone Lookup by Coordinate