The sea between Ibiza and Formentera is the shortest of the Balearic crossings, and it ends at some of the clearest water in the Mediterranean. It is also a protected one: a marine reserve, a natural park and a seagrass meadow set the rules for where you can anchor, how fast you can go and when you need to book. This guide covers what a skipper, or a guest on a charter, needs to know before leaving Ibiza.
The channel: Es Freus
Between the two islands lies Es Freus, a channel that is legally classed as a narrow channel. The Es Freus marine reserve, created by Decret 63/1999, protects the sea between the two islands. In the reserve, fishing and the extraction of marine life are restricted, and anchoring is banned in the maximum protection zone around the islet of s'Espardell.
Anchoring on Posidonia oceanica, the seagrass meadow that covers much of the sea floor here, is banned across the Balearic Islands. The anchoring and Posidonia guide explains the rules and the penalties.
Speed limits and bathing strips
- Port of La Savina. The limit inside the port is 6 knots, and on the approach 15 knots, reducing to 6.
- Beaches. Off a beach there is a bathing strip 200 m wide, and 50 m wide elsewhere along the coast. Inside it, the limit is 3 knots and no one may discharge anything. Inside the Ses Salines natural park, no vessel may navigate or anchor in the 200 m strip, and boats cross it only through the marked channels.
Where to moor or anchor
Formentera has two regulated buoy fields, both in the Ses Salines natural park and both run by Ports IB:
- Badia de s'Alga, at S'Espalmador, with 68 buoys.
- Es Caló de s'Oli on Formentera, in the south and innermost part of the cove, with 21.
A third field in the same group, Platja de ses Salines, is on Ibiza. The buoys are sized for different boat lengths, and the price list covers boats from 8 m to 25 m. A swim voucher is available for the smaller buoys only. Booking works like this:
- Online only at reservas.portsib.es. A phone call or an email is not accepted. You register, add your vessel with its registry documents, and pick a slot. A charter boat uses a boat code that the rental company gives you.
- Slots. A swim voucher covers a morning (10:00 to 14:00) or an afternoon (14:00 to 18:00), a day slot covers 10:00 to 18:00, and an overnight slot runs from 18:30 to 18:00 the next day. Overnight check-in is from 18:30 to 19:30.
- Limits. At most three nights per field, and the same boat cannot book the same field again within four days. You cannot anchor inside the field, the speed limit inside is 3 knots, and the field is not a shelter in bad weather: Ports IB cancels bookings when the weather turns.
- Season. The booking season has run from 1 June to 30 September, extendable to 15 October. In 2026 the fields opened late: the buoys were laid from 15 June and each field opened for booking once its buoys were in. Check the platform for the current dates.
- Outside the season. No booking is taken. The buoys still in the water are free to use until Ports IB takes them out for the winter, as Decret 25/2018 requires once they are not needed.
- Attendant. The buoy-field attendant answers on VHF channel 77 and works from 12:00 to 20:00 in the season.
Outside the buoy fields, the park plan lets you anchor on sand only, never on Posidonia, and you remain responsible for where your anchor lies. Anchoring of any kind is banned in the marine sector of Caló de s'Oli and in the southernmost part of Cala de sa Torreta, near S'Espalmador.
Landing at S'Espalmador. It is the one islet of the park where landing is allowed, and only through the entry and exit channels. Mud baths in the lagoon are prohibited, and so are dogs, camping and overnight stays on land.
La Savina
The port of La Savina is the only commercial port of Formentera, with the ferry quays and the marina. Local port control answers on VHF channel 9 and by phone on 971 322 130. Eivissa port control is on channel 13. Inside the port there are two navigation channels, and recreational craft up to 24 m long, 6 m wide and 2 m draught use the secondary channel; keep to the right half of the channel. Anchoring in the port waters is prohibited unless the port authority authorises it. The port guide covers the quays, parking and the marina.
Charter and licences
Since 1 October 2026 the exemption from the boating licence for boats up to 5 m and 15 hp applies to private use only. A rented boat needs a title, so confirm with the charter company what you are allowed to skipper. Charter boats also book buoys through a boat code supplied by the company.
Safety and radio
Channel 16 is for distress and safety only, never for conversation, and DSC distress alerts use channel 70. For an emergency at sea, call 900 202 202 (Salvamento Marítimo) or 112. The buoy-field attendants answer on channel 77. Plan with the weather page for the wind: a field is no shelter in a blow.