Advance rail tickets for Paddington to Penzance

I looked at nationalrail.co.uk, they have a train leaving Paddington Station, 3 minutes after every hour.
Buying advanced tickets you would save money. If your plane is scheduled to arrive early morning, book ticket for early afternoon, give yourself 3-4 hours gap time. You probably won’t need that much, but it’s better to have it, then worrying if you are going to make it.

Here is the official information about the Night Riviera.

https://www.gwr.com/plan-journey/journey-information/on-board/night-riviera-sleeper

You can't just rock up for that one, it sells out quite a long time ahead. If you plan on that you will need to be confident that your overseas flight won't be rescheduled or you could be out a fair amount of cash.

Another concern is that the Riviera pulls out of Paddington just before midnight, with access to the train from around 2100. If you suffer from jetlag will you be able to be up all the day of your arrival until quite late?

Day trains to Penzance are frequent and less expensive, but getting the ticket in advance comes with risks and waiting until the day costs more money.

You don't want a night in London on arrival and travel to the southwest the next day do you?

Thanks for the advice; staying in London (close to Paddington) or taking the (day) train and catching some sleep on the 5 hour trip might be the options. Jet lag is the main issue, we can only function for a few hours and then crash!

Then stay the night in London, enjoy a hearty breakfast the next day and off you go on your train ride, rested and fed. Loads of accommodation options by Paddington. Why push yourselves if jet lag is an issue? Remember you will on vacation, the time when you rest and relax.

To save $$’s buy both the following day Penzance tickets AND your Heathrow Express tickets in advance. I’ve PM’d you an accommodation option.

While you might not "need" a rail pass, the BritRail Southwest Pass looks like a reasonable value, starting from $189 per adult for 3 travel days spread over a month. Seniors, youths, or groups of 3 or more can get a discount. The pass includes the Heathrow Express assuming that you take it during those same 3 travel days. Compare this to 114 to 150 pounds for a daytime, roundtrip Paddington-Penzance ticket at Off-Peak (not Advance) rates. Or look at the Two Together or other discount Rail Cards (30 pounds, same link) that could get you about a 1/3 off most ticket prices, even on short notice.

My husband and I have actually done this. We arrived LHR and went directly to Paddington. We had advanced tickets to Penzance.
Our flight from the US was delayed 24 hours. So we had to pony up to get another set of tickets to Penzance. What we did not have is travel insurance so that we would be reimbursed for the expenses due to the delay.

I have gotten advance rail tickets many time since and never had this issue again. It has always made sense to us to get on the train, get away from the city and to where we want to start our vacation. We usually travel to an area we want to visit. The train ride allows us to unwind, we get a hotel less expensively than in London, and we waken the next day ready to roll. We generally rent cars and drive portions and sure don't want to rent a car directly off the flight with jetlag. We always do London at the end of the trip.

So my advice would be to allow several hours in case you have a delayed landing, and get the advance tickets...you save a bunch on the longer longer train rides. But I would also advise to have travel insurance ...

Plenty of advice about train travel in Britain here:>https://www.seat61.com/UK-train-travel.htm

Consider off-peak tickets instead of advanced tickets. They are not significantly more expensive and work on multiple trains so if you are early or late, they tickets should work.

could you explain how to purchase "off peak" vs "advanced"....I am plugging in our travel dates and destinations but do not see where this is offered via internet.

Go here and look at the text under the price of each ticket:

http://m.nationalrail.co.uk/pj/pj

If you're looking at RailEurope, don't do that. It doesn't always offer the less-expensive tickets and there's usually (always?) a substantial service charge. If you have trouble buying from the rail company website to which you are bounced by NationalRail, PayPal will probably work. Don't let PayPal convert the amount into dollars, however.

Alternatively, there are other sources that sell at the same or virtually the same price. You can try trainline.eu or loco2.com. (I haven't verified that they sell British tickets.)