A ferry timetable can look like a spreadsheet that has been through a washing machine. Asterisks, daggers, tiny superscript letters, footnotes set in type so small you need to hold the page up to the window. None of it is designed to trick you, but none of it is standardised either — which is why two operators can use the same symbol to mean two different things.

Ten minutes spent learning the key is worth it. Here is how the common markers work, and how to check a sailing properly before you commit to it.

Start with the grid, not the symbols

Before you decode anything, work out what the table is telling you. Rows are usually individual sailings; columns are usually days of the week or dates. The first thing to read is the validity period, often printed at the top of the page or in the file name. A timetable introduced in March may be replaced by a summer edition, and a PDF you saved last year is a trap rather than a reference.

Next, confirm which clock you are reading. Continental operators generally use the 24-hour clock; many UK ones print 12-hour times with am and pm, and some print both. Midnight is the usual stumbling block. A sailing listed at 00.30 departs in the small hours of the day named at the top of that column, not the evening before. Where a timetable shows 12.00am, treat it as midnight and check the neighbouring columns to be certain.

Departure and arrival times are almost always local to the port they refer to. On Dover to Calais, the arrival time is French time, an hour ahead of the UK for most of the year. A 07.00 departure arriving at 09.30 has therefore taken ninety minutes of sailing and an hour of time difference — not two and a half hours.

The symbols you will meet most often

Symbols are operator-specific, so treat the list below as a guide to common meanings rather than a universal code. Always find the key, usually at the foot of the page or behind a “Timetable key” link online.

• Asterisks, daggers and double daggers (*, †, ‡) — footnote markers. The number of them tells you how many notes apply, so a row marked ‡ sends you to a different note than one marked *.
• Superscript letters — a short code. “E” often means the sailing runs except on a named day; “S” often flags a seasonal, summer-only or school-holiday sailing.
• Dashes, dots or an “X” in a cell — no sailing on that day.
• Bold or shaded rows — frequently mark the fastest crossing, the busiest departure, or a sailing that must be reserved.
• Small icons — a bicycle, a car, a wheelchair, a plug. These describe facilities or restrictions rather than times.
• An “R”, “B” or “C” — often means reservation, booking or coach connection. Sometimes the same letter means the opposite. The key settles it.

Sailing codes: day letters and abbreviations

Many ferry timetables borrow railway shorthand, which is why you see strings like “Mo–Fr”, “SO” or “SX” in a column headed “Days”.

Day letters

Days may appear as Mo Tu We Th Fr Sa Su, as M T W T F S S, or as numbers. The single-letter version is genuinely ambiguous — T could be Tuesday or Thursday, S Saturday or Sunday — so a table using it will normally define the order in the key. Numbered days follow one of two conventions: Monday to Sunday as 1–7, or Sunday to Saturday as 1–7. Check before you plan around a “4”.

Common combinations

• D — daily, every day within the timetable’s validity period.
• MO, TU, SU — one specific day of the week.
• MF or Mo–Fr — Monday to Friday only.
• SO — Saturdays only.
• SX — every day except Saturday, from the railway phrase “Saturdays excepted”.

The pattern is easier than it looks: one letter for the day, X for “excepted”. Once you spot that, most codes decode themselves.

Ship and service codes: what you are actually booking

Underneath the time, timetables often name the vessel or the type of service. This matters more than it appears.

A conventional ferry or Ro-Ro is the classic car ferry: slower, usually roomier, with more to do on board. An HSC, catamaran or “fast craft” cuts crossing time but often carries tighter luggage rules and has less deck space. A passenger-only or foot-passenger service takes no vehicles at all, and on some routes it is the only option on a particular day.

You may also see route letters, such as two sailings between the same pair of ports listed as “A” and “B”. These are different services, occasionally using different berths or terminals within the same harbour, and sometimes with different check-in arrangements. If your ticket says sailing B, turn up for B.

Footnotes: where the real conditions live

The footnote is not small print to skip. It is where the timetable tells you the things that will actually disrupt your day: that a sailing is tidal and shifts by up to an hour either side of the printed time, that check-in closes thirty or forty-five minutes before departure, that the last crossing does not run on 25 December, or that onward coach and rail connections are only guaranteed on specific sailings.

Read the notes attached to your sailing, then read the general notes at the bottom of the table — the ones that apply to everything. Two minutes there beats an hour in a queue. Where a note mentions tides, weather or “operates subject to”, treat that sailing as a plan with a margin rather than a fixed appointment.

Four mistakes that catch people out

1. Using an expired timetable. Winter and summer editions can differ substantially, and a downloaded PDF does not update itself. Check the valid-from date each time you plan.
2. Assuming “daily” means every single day. Christmas Day, New Year’s Day and occasional maintenance dates are often excluded in a footnote you have not read.
3. Reading only the departure time. The number that decides whether you make the sailing is the check-in deadline, which can be well over an hour before departure for vehicles on longer routes.
4. Overlooking a restriction on your chosen sailing. A crossing can be freight-only, bicycle-only or marked as requiring a reservation, with the detail hidden in the notes column.

Before you book: a five-step check

1. Confirm the timetable is current by checking its valid-from and valid-to dates.
2. Find your day of travel, then read across the row: time, symbol, code, footnote marker.
3. Locate the key and decode every marker attached to that sailing.
4. Note the check-in time, then work backwards to plan your journey to the port, allowing for traffic and terminal transfers.
5. Book, then re-check the timetable the day before you travel, in case of a seasonal change or a known disruption.

Do that and a timetable stops being a puzzle. It becomes what it was always meant to be: a clear answer to a simple question — does a ferry leave when you need it to, and can you be on it?

Photo: Peggy_Marco / Pixabay