Do the arithmetic before you do anything else. Sail out of Penzance at 09:15, arrive on St Mary’s at about midday, and the ship leaves again at 16:30. That is roughly four and a half hours on the islands, bracketed by five and a half hours at sea. For some people that ratio is the whole point — the crossing is half the adventure, with dolphins off Land’s End and the Minack high on its cliff. For others, it is a long day for a short lunch on a sandbar.
An Isles of Scilly day trip can be one of the best days of a Cornish holiday or a slightly expensive disappointment, and the difference is almost entirely in the planning: which of the three ways to travel you choose, what you try to see in the time ashore, and whether you have been honest with yourself about the sea. This guide sets out the options, the real costs, what you can do in the hours you get, and when a day trip is the wrong answer.
The three ways to do it
| Option | Travel | Time ashore | Fares from |
|---|---|---|---|
| Sail both ways | Scillonian III from Penzance, out 09:15, back 16:30 | About 4½ hours | £35 adult, £17.50 child |
| Fly out, sail back | Skybus from Land’s End, Scillonian III home | Considerably more — the morning on the islands | Check when booking |
| Fly both ways | Skybus from Land’s End, Monday to Friday | The most of the three | £149 adult, £119 child |
On selected days in the season the operator also runs double sailings that stretch the time ashore to as much as seven hours and forty-five minutes. If your dates are flexible, those days are the best value of all — check the timetable for them before you choose a date.
Option one: sail both ways
The classic, the cheapest, and the one the ferry timetable was built around. The Scillonian III leaves Penzance at 09:15, reaches St Mary’s around midday, and sails home at 16:30, getting back to Penzance at about ten past seven. Day-trip fares start from about £35 for an adult, £17.50 for a child, £10.50 for an infant and £15 for a dog.
The crossing is a genuine highlight on a good day. You pass across Mount’s Bay, along the Penwith cliffs past Mousehole, Lamorna and Porthcurno, round Land’s End and out past the Wolf Rock, with a real chance of dolphins and seabirds and, in summer, the odd basking shark. Our Scillonian ferry guide covers the crossing, the check-in and the luggage in detail.
The downside is time and sea. Four and a half hours ashore is enough for St Mary’s but not really for anywhere else, and you cross twice in one day. On a calm day that is a pleasure. On a lumpy day, it is five and a half hours of a shallow-draught ship rolling in an Atlantic swell, and a day-tripper who is sick on the way out has to face the same crossing again that afternoon.
Option two: fly out, sail back
For most day-trippers this is the best of the three, and it is the one the operator promotes as a package. You fly from Land’s End Airport on a Skybus Twin Otter — a twenty-minute flight, low over the Penwith coast and across the sea to St Mary’s — and come home on the Scillonian in the afternoon. A transfer runs from Penzance station to Land’s End Airport for anyone without a car.
The gain is the morning. Arriving by air puts you on the islands hours before the ferry, which is the difference between a St Mary’s day and a proper island day — early enough to catch the inter-island boats, which leave St Mary’s Quay at around ten, and still have time for lunch and a walk. You also keep the best of the ferry: the slow return, the Cornish coast rising out of the sea, and dolphins if you are lucky.
The risk is fog. Skybus is a small aircraft on a short runway and fog is the routine cause of delays and cancellations. If the morning flight does not go, check what the operator offers before you set off, and have a plan for the day if you end up on the mainland. Prices for the fly-sail combination are not published as a simple fare, so compare them when you book.
Option three: fly both ways
The Skybus day trip flies from Land’s End on weekdays, Monday to Friday, and is bookable up to seven days in advance. Fares start from £149 for an adult, £119 for a child, £52 for an infant and £106 for a dog.
It gives you the most time on the islands, no seasickness at all, and a spectacular pair of flights. It is also four times the price of the ferry and doubly exposed to fog, and at that point it is worth asking whether one night on the islands would not be better value. For a family of four the fly-fly day trip costs more than many nights’ accommodation.
What you can realistically do in a day
If you have four and a half hours
You have St Mary’s, and that is enough to fill a very good afternoon. The quay is in Hugh Town, the main settlement, a small granite town squeezed onto a sandbar with a beach on each side. Within the time you can comfortably:
- Walk the Garrison — the headland above the harbour, ringed by eighteenth-century walls and gun batteries, with views across to the other islands. About an hour and a half at a relaxed pace, starting from the top of the town.
- Eat lunch in Hugh Town and swim or sit on Porthcressa, the beach on the south side of the sandbar.
- Walk to Peninnis Head, with its wind-carved granite, and back through Old Town.
- Visit the Isles of Scilly Museum and the shops.
- Hire a bike or take a taxi to Pelistry Bay on the far side of the island.
Choose two of those, not five. The temptation is to try to see everything, and the result is a day spent looking at a watch.
Can you get to an off-island?
This is the question that trips people up. The inter-island boats of the St Mary’s Boatmen’s Association leave St Mary’s Quay at around ten in the morning, with returns in the late afternoon, and the day’s sailings are chalked on boards on the quay. If you arrive on the midday ferry, the morning departures have gone. On some days there are sailings that would let a day-tripper reach an off-island and be back for the 16:30 ferry; on many days there are not, and even when there are, the time ashore is short and the margin for getting back is thin.
The honest advice is this. If you sail both ways, plan a St Mary’s day and treat anything else as a bonus decided on the quay. If seeing Tresco, Bryher or St Martin’s is the point, fly out, or stay a night.
Tresco Abbey Garden in a day
Tresco Abbey Garden is the single most popular reason for a day trip, and it needs at least two hours to do properly. It is open daily from 10:00 to 16:00 from mid-March to the end of October, with last entry at 15:15, and admission is £18 for adults, £5 for under-16s and free for under-5s, paid at the gate. For a sail-both-ways day-tripper, getting from the midday ferry to Tresco, round the garden and back to St Mary’s for 16:30 is at best tight and at worst impossible, depending on that day’s boats. Flying out makes it realistic. If gardens are your reason for coming, our guide to the best gardens in Cornwall puts Tresco in context with the mainland ones.
A sample day on St Mary’s
- 08:15 — breakfast in Penzance, walk to the quay.
- 08:15–09:00 — check in (it opens an hour before sailing and closes fifteen minutes before).
- 09:15 — sail. Get on the outside deck for the first hour.
- c. 12:00 — arrive at St Mary’s. Walk straight up to the Garrison while everyone else heads for lunch.
- 13:30 — lunch in Hugh Town.
- 14:30 — Porthcressa beach, or the walk out to Peninnis Head.
- 16:00 — back at the quay. Do not cut it finer than this.
- 16:30 — sail home, with a warm layer on and a lookout for dolphins.
- c. 19:10 — back in Penzance.
What it costs, honestly
For one adult sailing both ways, the day starts from around £35 plus parking in Penzance, lunch and anything you buy. That is good value for a day that includes five and a half hours of one of Britain’s best coastal voyages.
For a family of two adults and two children, the ferry fare alone starts at around £105, before parking and food. Fly-sail costs more; fly-fly starts from over £500 for the same family. At that level, it is worth pricing a single night on St Mary’s, which would give a whole afternoon, an evening, a morning and the chance to see an off-island, for not a great deal more.
Parking in Penzance is at Cornwall Council’s Harbour and St Anthony’s Gardens car parks, both under 800 metres from the quay, or at a park-and-ride about 1.7 miles out of town.
Weather, and what happens when it goes wrong
Every version of the day trip depends on the weather. The ferry can be cancelled or its schedule changed in heavy seas, particularly in spring and autumn. The planes do not fly in fog, and fog on Scilly can appear in otherwise good weather, especially in early summer. Check the operator’s service status the evening before and again on the morning.
The other weather factor is comfort. A crossing in a big westerly swell is hard work, and a day trip means doing it twice. If you are prone to seasickness and the forecast shows wind, either fly or postpone. Our Cornwall weather month by month guide explains what each month tends to bring.
If you are travelling on to anywhere after the trip — a train home, a flight — do not make the day trip your last day. Give yourself a buffer.
Practical tips
- Book in advance for summer and especially for Saturdays, when the ship fills with people starting a week on the islands.
- Stay the night before in Penzance. A 09:15 sailing from anywhere further than half an hour away is a dawn start. The Penzance guide has the town, and our guide to getting to Cornwall covers the train, which stops a short walk from the quay.
- Take seasickness tablets before boarding if you are at all prone.
- Take a warm layer and a waterproof even in summer. The deck is cold and the islands are exposed.
- Take some cash. Card acceptance is widespread but not universal, and there are very few cash machines.
- Eat on the island, but bring a snack for the crossing.
- Be back at the quay by 16:00. The ship does not wait for day-trippers who have lost track of time.
- Remember there are no lifeguards on any Scilly beach if you plan to swim.
Is an Isles of Scilly day trip worth it?
Yes, if the crossing is part of what you want. A calm day on the Scillonian, with dolphins in the bow wave and the islands appearing on the horizon, followed by a walk round the Garrison and lunch in Hugh Town, is a superb day out and one of the most memorable things you can do from a Cornish holiday base. Wildlife lovers in particular get a great deal from the voyage — our seal watching guide covers what else to look for along the coast.
It is less worth it if you want to see the islands rather than St Mary’s, if you are a poor sailor, or if you are paying for a family on the planes. In those cases, one or two nights on the islands will give you a far better experience for the money. Our full Isles of Scilly guide covers staying longer, the five inhabited islands and how the inter-island boats work.
And it is not worth it at all in a strong westerly with a poor forecast. Postpone, go to the Minack or St Michael’s Mount instead, and try again another day. The islands will still be there, and the sea will have calmed down.
Frequently Asked Questions
How long do you get on the Isles of Scilly on a day trip?
About four and a half hours if you sail both ways: you arrive at around midday and the ferry leaves at 16:30. Flying out gives you most of the morning as well, and selected double-sailing days offer up to seven hours and forty-five minutes ashore.
How much does a day trip cost?
Sailing both ways starts from around £35 for an adult and £17.50 for a child. The Skybus fly-both-ways day trip starts from £149 for an adult and £119 for a child. Fly-sail prices sit in between; check when booking.
Can you visit Tresco on a day trip?
It is possible but tight on a sail-both-ways day, because the inter-island boats leave St Mary’s in the morning, before the ferry arrives. Flying out makes a Tresco day, including the Abbey Garden, far more realistic.
Is the day trip worth it if I get seasick?
Sailing both ways means about five and a half hours at sea in one day, so probably not. Fly at least one way, or choose a calm day and take tablets before boarding.
Can I take my dog on a day trip?
Yes. Dogs sail on the Scillonian from around £15 and can fly on the Skybus day trip from Land’s End from £106.
Do I need to book in advance?
For summer, yes — especially Saturdays and school holidays. Skybus day trips are bookable up to seven days ahead.
What happens if the weather is bad?
Ferries can be cancelled or rescheduled in heavy seas and flights are delayed or cancelled by fog. Check the service status the evening before and on the morning, and keep your plans flexible.
What is the best thing to do on a day trip to St Mary’s?
Walk the Garrison above Hugh Town for the views across the islands, then have lunch and a swim on Porthcressa beach. It fits the time comfortably and shows you what the islands are like.
Pick the day by the forecast rather than the calendar, fly out if you can, and plan an afternoon that fits the hours rather than a list that does not. Done that way, a day on the islands feels far longer than four and a half hours — and there is a good chance it will end with you on the ferry home, watching the islands disappear, already working out when you can come back for a week.
Before booking a fly-out day trip, check the luggage rules: day-trip tickets on Skybus include no hold luggage at all, and the hand-luggage limit is 3 kg in a bag no bigger than 30 x 15 x 15 cm. Our guide to flights to the Isles of Scilly covers the rules, check-in times and fog delays in full.
If the garden is the reason for your trip, read our Tresco Abbey Garden guide before you book. It explains which boat landings are closest to the gate, why the 15:15 last entry matters so much to day-trippers, and how long you really need inside.
Photo credits: Old Grimsby, Tresco — Old Grimsby beach 2 Isles of Scilly by Kernow Skies, CC BY-SA 3.0 (licence). Inter-island launch — Passing Stoney Island, Isles of Scilly by Peter Trimming, CC BY-SA 2.0 (licence). Hugh Town harbour — Isles of Scilly, St Mary’s – Hugh Town harbour by Chris Gorringe, CC BY-SA 2.0 (licence).