Ferry from Calais to Dover

Have a read of this

https://www.seat61.com/trains-and-routes/london-to-paris-by-ferry.htm#Why_go_by_train_&_ferry

You can do it, but it's not the most efficient way of crossing the Channel these days.

Thanks so much for the bountiful reply. You provided some enticing options.

the short version is that there are three ferry companies between Dover and Calais, P&O, Irish, and DFDS... but only P&O take foot passengers, but even they only on the service on a few of their crossings. And then you might have qualms with the way they fired all their crews on zero notice, failed seaworthy tests and replaced all the crew with temporary untrained workers from India.

If that's ok, then you just need to find a way from the SNCF station in Calais to the ship - it isn't close - and a way from the ship to Dover station, again not close.

Dramatically easier to take the train (where will you be coming from?) to either Paris gare du Nord or easier Lille and get the Eurostar train direct and nonstop into London St Pancras International.

Or you could take the train up the coast through Belgium into the Netherlands to Rotterdam and change into the Metro at Schiedam to the Hook of Holland where the train stops right at the boarding area for the Stena Lines ferry (twice a day at 2:15 pm and about 9pm) which takes you right to the train station at Harwich, Essex where there are trains direct to London Liverpool Street Station in the business area of London. For today and tomorrow there is a sale on for £15 foot passenger fares, on daytime crossings only.

Can you say what is calling you to/take a Calais Dover foot passenger crossing?

I make those crossings frequently but never as a foot passenger.

The easy way to do the crossing (which the Man in Seat 61 won't tell you as he doesn't do buses) is to take the Flixbus from Paris Bercy or Lille to London. They tell you which of the three ferry companies (or the tunnel) they are taking when you book- which depends on the service and the day of the week.
That way you don't have to bother with the bus transfer at Calais (the Baladin) from Calais Ville station to the port.

EDIT- There are also overnight ferries from Le Havre to Portsmouth 4 days a week, and from Cherbourg to Portsmouth (both Brittany Ferries routes) on a Sunday, also a lunchtime Cherbourg to Portsmouth on some other days- although the rail connection from Paris is a bit tight for the lunchtime ferry. These are additional routes to those listed by The Man in Seat 61

Thanks Nigel for your reply. I actually am taking the train from Munich early in the day and thought I would do something different for my annual trip to England. I enjoy land travel and like the ferries.

To take the Flixbus is an interesting proposal as it would mean the use of only one vehicle from Paris to London if it were not my aversion to busses for long distances. Thanks to isnc31.

If you at starting in Munich that day that settles the question. It is impossible to get to Calais in time for the last London ferry connection.
So you are either on the Harwich ferry (a 4 train ride from Munich) or on one of the overnight boats from Northern France.
There is a direct Munich to Paris train at about 0700, arrives Paris at about 1230.
My own preference would be the St Malo to Portsmouth route.
But as the Munich train arrives at Paris Est the easiest connection would be on Eurostar from Paris Nord, on a train after 1430.