"best" months to fly? (costwise)

Hi all...well after 3 wks back in the States I am ready to start looking forward to/planning my next return to the UK!

For those of you who travel btwn our 2 countries regularly, when are the cheapest months to fly? I have always gone in late October or November and get great fares. But I'd like to do a spring visit this time.   
When do the fares start going up for the warm season?
If I aim for late March, is that too late?

thanks in advance...

In my experience fares fall dramatically after Labor Day in the US.... The colder it is the less people want to visit, I guess - I used to get really good deals coming over to visit in January and February. Not sure when they start going up, but I should think anytime after April or so?

I've always had the best luck getting cheap tickets in Feburary and November.  September and October used to be good, but they seem to sell out fast these day.  I did manage to get very cheap tickets in April once.  I think it was the week after Easter.  The week after a holiday seems to be a bit cheaper.

Any month with a big holiday or the summer is going to be expensive. The cheapest one I booked was in November and I booked it 1 month ahead of time,if I remember right it was $350 round trip

So far the only horrible months I have found are July and Aug.  I was looking for June flights to Boston from London and they were around the $450-$500 mark (Taxes included).  August I have seen as much as $1100 for the same flight.

the cheapest flight I  had  visiting the UK was in March.July was horribly expensive but then I was teaching and had no choice..

thanks ...

I am thinking of mid March, 2007 in practical terms, staying 3-4 months
Ideally I would like to spend less than $600


my ticket last autumn was $550 (ish) on Delta for a 4 month stay

please keep the suggestions coming!

Tickets are cheap for February/March and October/November...I've also seen prices drop to rock bottom right after Christmas (when I was looking at prices for an April trip) and then go back up by the end of January.

I don't do anything with fares, but I do know we (Delta) are pretty solidly booked all through the summer months. The only summer deal I think that might be out there is JFK-MAN as it's a new route and not fully booked yet.
Things fall off in Oct & early Nov. Feb & Mar are good months as well. April can be tough, depending on school breaks.
You might take a look at Virgin out of MCO since you're not too far from there.
You can also think of working on accumulating milage via credit card use--I have some friend that do this and put all of their business and personal expenses on an AMEX card for DL skymiles. They go to Europe yearly in business class with the milage.

I went with Delta my last trip and I know the person who charged it accumulated miles, but I'm not sure they'd be willing to let me use them! lol

the next flight won't be til next spring anyway unless something unexpected comes up

thanks for the comments

While September & October are cheaper than the Summer months, prices after Nov 1 tend to really drop.  This lasts until about December 15 when the Christmas fares kick in.

After New Years weekend the prices drop very low until Easter.  So watch out for when Easter is next year, if it is late March book before then, if it is in April anytime in March should be very cheap relatively.  March is the best month of the "cheap fare" months because it sometimes gets fairly warm and less rainy.  November, I think it the worst month for dull, rainy weather, no wonder it's cheap!

Yes, the Christmas fares are killer. You were asking about spring fares, but we haven't been back during that time, so I couldn't say. But if you plan to go for Christmas, try to leave before the middle of December. We went on Christmas Eve one year, which was kind of cool. The plane wasn't very full, the crew were all wearing Christmas caps/in a jolly mood, etc. We were jetlagged at the get-together on Christmas Day, but it was worth the savings that year.

The best fares I have found to Gatwick from Minneapolis, Minnesota have been right around $400-$440 round trip and were in November and March. I have traveled over those two months now for two years in a row and seem to find great deals then. I did however just find a July fare into Manchester for $600 which I have on hold for 2-1/2 more hours to decide if I am taking it or not. Good thing I put it on hold as the fare has already gone back up to $1223 on that very flight since last night!! 

so...did you get that fare silysnip?

we couldn't find any difference in rates avail online from early Sept to late October so he went ahead and took the one in early Sept.

so...did you get that fare silysnip?

I read it wrong, I have it on hold at the promotional price until 11pm on May 26th, jeez I have been stressing out here trying to hurry and decide what to do! Now I can drive myself crazy a little longer before I decide 

edited to say: Oops guess it was just holding the seats, I missed out on the fare before I even knew it, so went to book it now and found they did want to charge me the $1223! Off to look elsewhere to see if any other deals pop up