Ireland/Scotland/England--planning a trip for 2011

The really cheapest time to go is in the off-season (November-February). I have gone twice in February and had a great time (and some great weather), though you have to consider that some things will be closed or have reduced hours.

I prefer to go in April or May (or September or October). During these shoulder season months, most things are still open, the weather is good (but might be rainy) and there are still no crowds.

I would avoid June-July-August at all costs, unless you want to see gardens and such.

July is not a bad time to go. If you want to see Edinburgh, avoid August unless you have booked well ahead and LOVE crowds- due to the Festival/Tatoo. We also enjoy going in Nov/Dec. We just plan our days so that outside activities are in the middle of the day. We love the Christmas markets, so it was no problem for us.

Don't forget Wales. If you could swing a month, you could get a taste of it, too.

Last year my wife and I did London-Bath-Liverpool over Thanksgiving week. The weather was drizzly, but it always is in England. We even had a day of sunshine. Prices..well, we got a pretty good deal on airfare, though it still wasn't really cheap. Prices otherwise don't change much. I did notice that we got a pretty good deal on our first night's hotel across the street from Paddington Station. Everything seemed crowded as usual, but perhaps if we had ventured into more rural areas...the Cotswolds, for instance...we would have noticed a sharp difference from the summertime crowds. Frankly, we enjoyed getting away from the US during the frenzy leading up to Thanksgiving...no weeks of food prep, no guests to care for...just us.
I agree with the other poster who suggested shoulder season rather than the dead of winter...sure, airfare is cheaper in February than in October, but there is a reason...the days are very very short and the weather is very very dreary. Especially if it is to be your last trip, why not spend a few hundred extra (on a trip that will cost thousands regardless when you go) on reasonably decent weather for touring?

One thought: you aren't going to be able to even start to see all three countries in three weeks or 'maybe a bit' less.

We know we won't be able to see and do everything we'd like to in just 3 weeks, but that's all we'll be able to afford. Hadn't thought about the winter days being darker longer...very good point!

We just got back from a trip to Scotland and Northern England last week. I think that early June is a good time to go. We had great weather (in the 60s-70s most days) and the days are really long (does not get dark until about 11 PM and light by 4 AM) which makes driving easier. Also, Scottish schools don't let out until the last week in June and English schools the first week in July. We did not experience any crowds or long lines when we were there. We booked most of our lodgings about 3-4 months in advance and the prices seemed reasonable. What we did not realize is that the majority of attractions don't open until 10 AM and close around 5 PM, especially in the "off season", so plan on only seeing a couple sights in any given day.

I like September. You still have long days, the crowds are diminished, and actually many of the gardens still look spectacular. PAm