Summary

  • Ofcom will make the lower halves of maritime channels 27 and 28 available as two extra simplex assignments for coastal stations in early 2027.
  • One licensee already holds an authorisation involving these channels; Ofcom is arranging an alternative, and the converted channels will cease to be available for duplex assignment.

At a busy port, a radio channel is a working lane. Two ships and a shore station cannot wish a spare lane into existence when voice traffic backs up. Ofcom's 23 October maritime spectrum decision addresses local congestion by opening the lower-frequency portions of channel 27 at 157.350 MHz and channel 28 at 157.400 MHz for Coastal Station Radio (International) simplex use. The regulator expects applications to open in early 2027, after it updates its licensing system.

The distinction between modes matters. A simplex call uses one frequency in both directions. Duplex uses separate frequencies to transmit and receive. Ofcom says some UK areas have too few accessible simplex channels, causing congestion and conflict. It considered a wider conversion, waiting for digital maritime voice, and adding just two channels. It chose two, saying that route gives crowded locations relief while broadly preserving the balance between simplex and duplex capacity.

The new assignments will be first come, first served. Existing licensees seeking one must request a variation. But the two channels do not start from a clean slate: Ofcom says one licensee already has an authorisation for the channels covered by the decision. It is engaging that holder on alternative frequencies. Once the new simplex assignments enter the coastal-station licence, channels 27 and 28 will no longer be offered for duplex-mode assignment. The regulator has therefore created room in one lane by closing another.

The consultation docket shows why a tidy frequency table is only the beginning. Port of London Authority welcomed the added flexibility but warned against steadily draining duplex capacity. The UK Chamber of Shipping wanted the incumbent properly coordinated, compensated and given an equivalent clean duplex assignment. Those demands describe the cost of making the change real; the statement records Ofcom's direct engagement, not a completed migration.

Ofcom says it may enable more simplex channels if congestion persists. For now, the concrete promise is two frequencies and an early-2027 application path. The first useful evidence will be the updated licence system and a workable alternative for the existing holder.

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