Three hours from central London to Gatwick flight

The problem is that the train situation can change very quickly and with no warning.
I once dropped DD of at East Croydon station - the trains were absolutely fine when she got out of the car. Literally 100 yards to the platform - every train was cancelled.
When I have to be anywhere time-specific using the trains, I leave plenty of extra time. If it's to catch a flight I will building in several extra hours, just in case. I would rather spend ages in the departures waiting than missing the flight completely.

I would do it but I would go for Gatwick express rather than Thameslink and if the show overruns (unlikely) just leave the theatre early.

This would slow you down the most I think, unless you have aisle seats you won’t be able to get out very quickly. How sharp are your elbows?

I would say that in the years I travelled weekly to Gatwick I only had problems maybe twice? And both times I knew in advance that there was a major issue and managed to make other arrangements. A few more times I ended up crammed on to a very full Gatwick Express but got there. If there's a total block on the line there's a chance you'd know about it before the play started and could make a decision then about how to get to LGW/home. (I did always walk into Victoria semi-braced for a disaster on the departures board though.)

No, the biggest unknown is will there be problems with the trains? No one can predict that (including the rail services). 9 times out of 10 you’ll be fine. But that 10th time could mean you miss your flight. So down to you to decide depending on what the personal impact is if you miss your flight and how risk averse you are.

If there is an issue with the Charing Cross train, get a taxi to Waterloo,
train to Clapham junction, where you can get a train to Gatwick. You could do it, but it would be tight and would depend on your appetite for stress !

https://www.bbc.co.uk/news/articles/cy9xj3vnyxgo

just the other day

Personally, I think you’ll be fine. If you get the 1700 train , you’ll be through security and at the gate by 1810 latest. I’d risk it. Only question I’d ponder is whether to buy fast track security.

Once at LGW you'll only need to get the shuttle over and then go through security before you get to the gate. If you're capable of power walking then the walk to the gate won't do you in - even the furthest gates are only ten minutes at a quick pace and good use of the travelators. It's the journey there that's the unpredictable bit. I'd agree with others that the East Croydon line is the potential single point of failure. I'd always prefer to be at Victoria with a choice of services than rely purely on Thameslink, if only because I used to do this journey weekly and if services are really pushed but still moving they prioritise the Gatwick Express over the regular trains.

I used to commute down that way. Spent a lot of time sitting on the platform at East Croydon station.

Don't have much to add, except that I'd leave the performance before the encore (definitely sit at the end of a row) to save time getting out of the theatre.

Why would you do that to yourself? If you must, Tottenham Court Rd/Elizabeth line to Farringdon, then Thameslink to Gatwick is the quickest route I know of

Baggage has to be checked in an hour before flight so you only really have 2 hours unless it’s hand luggage only. That is cutting it very fine and banks on no delay to start time of the performance.

Cutting it way too fine.

If you leave at 1630 on time from central London, have no luggage, and you’re already checked in then you can be at Gatwick by just after 6. But you are cutting it very fine. I wouldn’t want the stress.

We normally do Charing Cross to London Bridge or Waterloo(over the bridge) to Clapham Junction and pick up mainline service in that direction. Alternatively tube Embankment to Victoria. You can also change at East Croydon to take first available trains.

Well, as a semi helpful data point I left a restaurant in Soho on Friday night just after 10, walked to Green Park, got the tube to Victoria then a train to Brighton (via Gatwick). I was in Brighton just after midnight, so about 2 hours. On that basis I'd happily go to Gatwick as there's no real need to be a LGW any more than an hour before a domestic flight IME.

From Covent Garden area I'd probably walk to TCR, get the Elizabeth line to Farringdon and pick up a Thames Link service from there. I'd be surprised if that took much more than an hour, leaving an hour to spare :)

You can get a premier inn by Gatwick for about 125 or B and Bs at nearby HORLEY from about 60.

😂 indeed. They’re all unreliable. It’s a service I use often too, Thameslink. Though I prefer Victoria express when it works.

You don’t have to change tubes to get to Victoria. It’s less than 5 mins walk from the Trafalgar theatre to Embankment then just 3 stops. I would do it.

It’s the service I use to get into London and it doesn’t appear any less reliable than any other, I certainly haven’t found it to be the case. Thing is @sparkysdream you just have no scope for anything to go wrong at any point whichever train service you choose. Why subject yourself to such stress when you don’t have to?

Pretty much the only difference with Gatwick Express is it doesn't stop at East Croydon. And costs loads more.

Theatre shows rarely run late.

I'd do it.

Pretty much the only difference with Gatwick Express is it doesn't stop at East Croydon. And costs loads more.

Theatre shows rarely run late.

I'd do it.

The Gatwick Express uses the same rails so if the problem is signals, points, another broken down train or an obstruction on the line, no train is getting there.
Southern and Thameslink seem to have additional problems with lack of staff and/or lack of trains.

It’s fine. There is a choice of trains to LGW. Gatwick Express is quickest but costs most. Plenty of Thameslinks and Southern only make 2/3 stops and take about 45 minutes. Which theatre , as it could easily take as long to get to a mainline London station at that time,

If the trains are running as everyone has said it should be easy, but it takes so little for Thameslink to fall over and not function I’m not sure I could relax and enjoy the show. Victoria is a good backup (or possibly even preferable with Gatwick Express) and it’s a very quick hop from embankment on the district/circle line. If I was going to do this I’d be out of the theatre very fast and using Google maps to give me the best route to Gatwick so that you’re up to date on which trains are running. But if there is an issue at East Croydon which catches both train lines you’re knackered as there is no quick back up. Car journey is at least an hour.