Madrid museums

I went to all 3 museums about 10 years ago, so can’t really comment on how crowded they all would be. Well, the Prado will definitely be crowded. The Reina Sofia was not crowded on the day we went. Something to consider is buying the Paseo del Arte ticket that gets you into all 3 museums (1 entrance for each museum). It’s €32.80 and you can buy it on the Prado Museum website where you will choose your entry date and time for that museum.
I’m not sure if timed tickets are required for the other 2 museums, so you would want to check their websites.

The museums will be just as crowded during the free hours as any hour. The last times we visited the Prado (2022) and Reina Sofía (2011) it was during the free hours. We just got in line 30-40 minutes before the free admission opening. We had been to each museum previously so the free admission hours were sufficient. If you’re art enthusiasts you may want more time in each.

We were at the Reina Sofia last May and are in the over 65 age group. We just did walk up in the afternoon. There was no line and we just walked in after stopping at the admissions desk. We may have had to show passports, but I think they just looked at us and knew we were over 65. The area around “Guernica” was crowded ( nothing like the Mona Lisa) but that was the only place we ran into crowds in the museum and they were mostly young people.

Thanks all for your tips.

I found (somewhere, I can't recall where) this suggestion on how to see Guernica without crowds:

1. Get a timed ticket for 10am on the Reina Sofia website, it will be 12 Euros.
2. Go the entrance on Rda. de Atocha, the south side of the museum facing the street. There's going to be a metal gate blocking you from walking into the courtyard if you arrived before 10am. The courtyard has the main entrance, a small outdoor cafe, the entrance to the library and the ticket office.
3. Walk past the ticket office to the entrance where they'll scan your ticket.
4. Take the elevator on the right to the 2nd floor. You'll have to scan your ticket again to enter the permanent collections on the 2nd floor. Guernica is in room 205-10, it's pretty impossible to miss, and it's noted on the map.

I'm assuming I can do that with a Paseo del Arte ticket, but not with a free Senior Ticket, which can't be bought in advance.

During the free hours, there is usually a line to get into the Reina Sofia at the main
plaza. But the south gate is usually empty, so you can walk right in. There is no risk
of not getting in (barring a holiday in Spain or something like that), but you have to
get screened, so the time you have may depend on the line.

I found the Prado to be more crowded during free hours than the Reina Sofia. If you
are patient (and maybe a bit lucky), by 8:30pm or so, you may have Guernica more
or less to yourself (I did).

If you like art, the Real Academia de Bellas Artes de San Fernando is often overlooked. It’s huge, but you are often alone with the art. Very high quality.