seeking information: ticket for Buckingham palace

http://tickets.royalcollection.org.uk/

I don't know if booking tickets in advance is actually necessary. Anyone else have experience?

Buckingham Palace open for visits til 2nd October. Definitely book ahead to secure tickets and avoid queues. All your info here ...
https://www.royalcollection.org.uk/visit/the-state-rooms-buckingham-palace/plan-your-visit
I did it in 2011 - well worth it.

I did the tour last week when I was in London. It was definitely worth it. We bought our tickets online (you are given a time of entry) which is what you want to do for anything in London. The Palace is majestic. We went to Buckingham at 11:45 and were also able to go to Windsor Castle later in the day. A word of advice when you go to Windsor Castle, see St. George's Chapel first since it closes at 4pm while the rest of the Castle closes at 5:30. When we were entering Buckingham Palace, we were able to see the mad house that occurs while waiting for the Changing of the Guard. Too crowded!

thank you everyone for your replies. I was looking at options and the tickets are for the following tours:
1. state palace
2. palace and gardens tour
3. Evening tour
4. royal day out including state rooms, queen's gallery and royal mews
is it worth to do the royal day out or the evening tour? otherwise I was looking for guided tour of palace and garden and unfortunately this option is sold out for the day.
please advise
sincerely
Reema

Had been to Buckingham Palace the first year it had opened and vaguely remembered it aside from the fact that it was crowded. On a more recent trip to London I'd done the state room visit during December visit, it was very pricey and in a small group. I opted to visit during the day to get a glimpse of the gardens too. There isn't much to see of the gardens from windows inside the palace along the tour route.

My advice, if the Queen's Gallery and Royal Mews appeal, book the ticket with all three sights, but be prepared to spend the day or the better part of it visiting these sights. If the Queen's Gallery and Royal Mews don't appeal, book the evening tour, you'll still get to see the palace's interior regardless of the time of day you visit.

Others may know better, but I don't think the gardens are anything special. If you are especially interested in paintings and horses, then splurge with the Royal Day Out. I was quite happy with just the State Apartments, taking approx 2 hours for my visit.

You absolutely need to book in advance...they were turning people away last time we went.
If I recall correctly, you exit the palace tour out of the back of the palace and follow a path through the gardens to leave the grounds out of the back walls surrounding them. The gardens are pretty but nothing opulent or particularly unique.

Here is the link to the exhibitions at the Queens Gallery. In my experience, I would only book the Royal Day Out ticket if you are interested in the exhibition. If it is not your cup of tea art-wise, then I would skip this.

https://www.royalcollection.org.uk/collection/themes/exhibitions/scottish-artists-1750-1900/the-queens-gallery-buckingham-palace

https://www.royalcollection.org.uk/collection/themes/exhibitions/maria-merians-butterflies/the-queens-gallery-buckingham-palace

I do love to visit Buckingham Palace. There is also a special exhibition during the tour as well. This year it is 90 years of style from the Queen's Wardrobe.

https://www.royalcollection.org.uk/collection/themes/exhibitions/fashioning-a-reign-90-years-of-style-from-the-queens-wardrobe-0

thank you so much for your replies. it really helped to plan my trip. sincerely