hotel near Heathrow easy to access for old folks like me

I recently stayed at the not too expensive Holiday Inn Express at Terminal 4, and would stay there again.
https://www.ihg.com/holidayinnexpress/hotels/gb/en/hounslow/lonrs/hoteldetail?cm_mmc=GoogleMaps-_-EX-_-GB-_-LONRS

Traveling between terminals was pretty easy. There are machines that dispense free tickets to use the tube for that purpose.

Last month I stayed at the Hilton Garden Inn at Terminal 2. I've gotten addicted to the convenience! Just across a small parking lot from Terminal 2. I've stayed there before, and the service is always top notch.

We are booked in United and we are staying at Hilton garden inn. This is in December. I same way. Want the easiest way and convenience. Good luck

First of all, the 90 day ahead rule for the Heathrow Express is no longer accurate. They have a certain number of discount tickets that are available for advance sale and when they are gone, they are gone. Sometimes this is further out than 90 days.
I'd start looking earlier than the 90 days. I would quite surprised with a group that is your size if a cab might not come out about the same as the Heathrow Express. The Elizabeth Line is also an option.

It is fairly easy to transfer between terminals at Heathrow Airport. You can take the Heathrow Express or the Underground for free between terminals. You find a special ticket machine near the entrance to either that gives free tickets for transfers between terminals.

I stayed at the Holiday Inn Express at Terminal 4 last summer and found it satisfactory. One gets to it by a covered walkway from the terminal. Next to it are the Crowne Plaza, a little further along is the Premier Inn Terminal 4. I would go to restaurant in the Crowne Plaza over the one in the Holiday Inn Express.

We stayed at the Hilton Garden Inn before our early AM United flight last year. Just a 3-minute walk across a covered airport parking lot to get to Terminal 2. You will find it very convenient.

I stayed at the Hilton Garden Inn at terminal 2 about a half a dozen times and I've also stayed at the Sofitel at terminal 5 a few times.

Neither is cheap. To find the cheaper hotels, you need to stay on bath Rood and take a bus from your hotel to the terminals. I've never stayed there so I can't recommend the specific hotel.

Instead of the Heathrow express, you can take the Elizabeth line which runs basically the same route, but takes a few minutes longer. It's also cheaper than full price Heathrow Express if you can't get discounted tickets.

What time are your flights?

For ease and convenience I would pay the extra and stay at one of the on site airport hotels. It really does make the morning so much easier and less stressful.

In the past the (newish) Premier Inn at T4 has been extremely reasonable--well inder £100 per night. I've had no need to stay there since 2019, however, and I think rates are higher now. Usually you can get quite a low rate if you book early.

The hotel is accessed directly from the terminal via an enclosed walkway. It's not a short walk--maybe 10 minutes. It sounds as if the Hilton Garden Inn right outside T2 would require less walking, but I've never stayed there.

The large beds at the T4 Premier Inn are extremely comfortable. I don't know whether the hotel accepts more than 2 people in a room. The day bed (not a folding couch) was perfectly comfortable for me, but not in the same class as the large bed.

Premier Inn offers rates with several different cancellation options. Be careful about which you choose. I'd suggest booking however many rooms you need right away at the fully cancellable rate while you do further research.

If you are coming into Kings Cross by train from Edinburgh (most likely) the Piccadilly Line will be the easiest as you won't have any changes and the frequency is higher, and there is step free access. Also brings into play sone hotels along the route not far from Heathrow such as the Hilton GI at Hatton Cross or the Travelodge at Hounslow Central.

We always stay at the Sofitel at LHR, walkable to Terminal 5. Yes you pay more but for total convenience, excellent service and assistance and nice dining options we always have stayed there.

When do the flights leave? Staying somewhere in London and go to the airport the next day sounds like a nicer option.

But if you still plan to stay at the airport, the tube direct from King's Cross to Heathrow sounds like the easiest option.

We stayed in the Aerotel which is literally in terminal 3. The hourly rate was very reasonable. We only needed to be there for 12 hours because we had a 7 am flight. Downside was that there weren’t a lot of options for dinner. We ended up just getting some sandwiches at the M & S store that was also in T3. And the room was very small, but that didn’t concern us with such a short stay.

Yes, I've thought about the Hatton Cross possibility since the metro stops so close to hotels.

Several of you have asked about flight timing. Our earliest flight is 11:40, so needing to arrive at airport at 8:40. I think that part of the family would have a hard time leaving downtown London early enough.

I have looked at the Holiday Inn Express that several of you mentioned. For the 5 of us, it would be $900+. Several hotels on Bath road are under $500 for us all. I didn't know about the other hotels mentioned that are connected by walkway. 10 min walk indoors is not as big a deal as on/off busses. I'll look into those. I have also considered an uber from hotel to airport. Uber plus $500 hotel is a better deal than $900.

Thank you all for your help. We will take the Piccadilly line as you have suggested. I have booked the Premiere Inn at Terminal 4. We can walk into the terminal and take the tube to our desired terminals. This sounds like such a simple solution!

After posting above, I realized I should go ahead and book a room at Heathrow as part of a trip in February. The Holiday Inn Express I suggested above was considerably more expensive than the Premier Inn T4, so PI it is.

Liz, that's weird. I booked a room at the HIE (Terminal 4) for late April of next year for £102. That was less expensive than the nearby PI I checked out, it includes breakfast and is a refundable rate.

Any of the Premier Inns scattered around Heathrow would be a good choice.
We've stayed at the one near T4 several times and liked it, but last trip we stayed in the one near T5 which was a short walk to the village of Hammondsworth where there a couple of convivial pubs for lunch, dinner, or just a pint. There's a nice park there too if you fancy stretching your legs a bit.
Might mention that there's a system of minicabs around the airport that makes for cheap and efficient door to door service from the hotel to the terminals which we've found to be a terrific option when horsing luggage around. The hotel can book one for you.

Mardee, I guess prices are really date dependent. For a Monday mid February PI was £47 ( but minus breakfast) and HIE was £68.