The following table is adapted from the International Telecommunications Union Radio Regulations Appendix 18, including changes adopted by the 2007 World Radio Conference. Transmission on frequencies or channels shown in blue are not allowed within U.S. territorial waters, but are allowed on the high seas and in most other countries. Note that a marine radio operating in the international mode on a channel in which the ship station frequency is shown in black and the shore station frequency shown in blue would not be able to communicate with a U.S. shore station. Frequencies and channels shown in green were auctioned in the U.S. and are only available from the auction winner. The large number of "blue" and "green" channels and frequencies indicates the shortage of VHF maritime spectrum in the U.S. compared to most other maritime countries.

NOTES REFERED TO FROM THE TABLE ABOVE

1. Administrations may designate frequencies in the intership, port operations and ship movement services for use by light aircraft and helicopters to communicate with ships or participating coast station in predominantly maritime support operations under the conditions specified in Nos. 51.69, 51.73, 51.74, 51.75, 51.76, 51.77 and 51.78. However, the use of the channels which are shared with public correspondence shall be subject to prior agreement between interested and affected administrations.
2. The channels of the present Appendix, with the exception of channels 06, 13, 15, 16, 17, 70, 75 and 76, may also be used for highspeed data and facsimile transmissions, subject to special arrangement between interested and affected administrations.
3. The channels of the present Appendix, but preferably channel 28 and with exception of channels 06, 13, 15, 16, 17, 70, 75 and 76, may be used for direct-printing telegraphy and data transmission, subject to special arrangement between interested and affected administrations.
4. The frequencies in this table may also be used for radiocommunications on inland waterways in accordance with the conditions specified in No. 5.226.
5. Administrations having an urgent need to reduce local congestion may apply 12.5 kHz channel interleaving on a non-interference basis to 25 kHz channels, in accordance with the most recent version of Recommendation ITU-R M.1084, provided:

• It shall not affect the 25 kHz channels of the present Appendix maritime mobile distress and safety frequencies, especially the channels 06, 13, 15, 16, 17, and 70, nor the technical characteristics mentioned in Recommendation ITU-R M.489-2 for these channels;
• Implementation of 12.5 kHz channel interleaving and consequential national requirements shall be subject to coordination with affected administrations.

Specific notes

6. The frequencies 156.300 MHz (channel 06), 156.525 MHz (channel 70), 156.800 MHz (channel 16), 161.975 MHz (AIS 1) and 162.025 MHz (AIS 2) may also be used by aircraft stations for the purpose of search and rescue operations and other safety-related operations.
7. Channels 15 and 17 may also be used for on-board communications provided the effective radiated power does not exceed 1 W, and subject to the national regulations of the administration concerned when these channels are used in its territorial waters.
8. Within the European Maritime Area and in Canada these frequencies (channels 10, 67, 73) may also be used, if so required, by the individual administrations concerned, for communication between ship stations, aircraft stations and participating land stations engaged in coordinated search and rescue and anti-pollution operations in local areas, under the conditions specified in Nos. 51.69, 51.73, 51.74, 51.75, 51.76, 51.77 and 51.78.
9. The preferred first three frequencies for the purpose indicated in note a) are 156.450 MHz (channel 09), 156.625 MHz (channel 72) and 156.675 MHz (channel 73).
10. Channel (70) is to be used exclusively for digital selective calling for distress, safety and calling.
11. Channel 13 is designated for use on a world-wide basis as a navigation safety communication channel, primarily for intership navigation safety communications. It may also be used for the ship movement and port operations service subject to the national regulations of the administrations concerned.
12. The channels (AIS 1 and AIS 2) are used for an automatic identification system (AIS)  capable of providing worldwide operation, unless other frequencies are designated on a regional basis for this purpose.  Such use should be in accordance with the most recent version of Recommendation ITU-R M.1371.
13. These channels  may be operated as a single frequency channels, subject to coordination with affected administrations.
14. The use of these channels (75 and 76) should be restricted to navigation-related communications only and all precautions should be taken to avoid harmful interference to channel 16, e.g. by limiting the output power to 1 W or by means geographical separation.
15. These channels may be used to provide bands for new technologies, subject to coordination with affected administrations.  Stations using these channels or bands for new technologies shall not cause harmful interference to, and shall not claim protection from, other stations operating in accordance with Article 5. The design of such systems shall be such as to preclude the possibility of interference to the detection of AIS signals on 161.975 or 162.025 MHz.
16. Additionally, AIS 1 and AIS 2 may be used by the mobile-satellite service (Earth-to-space) for the reception of AIS transmissions from ships.
17. When using these channels (10 and 11), all precautions should be taken to avoid harmful interference to channel 70.