Save on airfare Plan your trip for spring or fall and spend up to $300 less per person than in summer, says Suzanne Rowan Kelleher, cofounder of the family travel site wejustgotback.com. England and Ireland are typically the cheapest countries to fly to from the U.S. In off-peak months, it's not hard to find a deal under $700 for a round-trip ticket (with taxes and fees) from the East Coast, $750 from the Midwest, and $800 from the West. A good reason to start in London: From there, you can get to other European countries through low-cost regional carriers like Ryanair and easyJet. Use momondo.com to compare prices for flights within Europe. "You can fly to almost any European country from London for under $150 round-trip," says McCarthy. "That's usually cheaper than the train." Also look into offers that combine airfare, hotel, and rental car. "In Europe, packages tend to be a very good value," says Saglie. "I see weeklong packages to Europe from the East Coast for under $1,000 per person, and under $800 from November through March."
Sleep cheaper Rooms at the Premier Inn, a chain with more than 600 locations in the U.K. and Ireland, look like they came out of your local IKEA and typically cost under $100 per night. The Hotel Novotel, also with hundreds of locations around the Continent, has larger rooms and a play area in the lobby, starting at around $150 per night. You might even be able to catch a deal at fancy yet family-friendly hotels like Grosvenor House, a JW Marriott Hotel next to London's Hyde Park (during fall and winter, rates can start at $144 per night).
Eat well for less Pick up groceries for in-room breakfasts and picnic lunches, suggests Tom Hall, the London-based director of online editorial for the Lonely Planet Travel guidebook series. "When I travel with my wife and kids ages 2 and 4, we buy enough food for a few days at the local farmers' market," he says. "It's cheap and fresh." Request a mini fridge when you book your hotel room (it's not standard in most chains) and ask the concierge for market suggestions. Also check out lfm.org.uk for a directory of London farmers' markets and provence-hideaway.com for a list of markets in France. What's more, many European museums have low-cost cafés with good food, he says. A family of four can eat at the restaurant at the Natural History Museum in London for less than $40.
Find freebies Take advantage of no-cost cultural activities. London's Royal Academy of Music offers free kid-friendly concerts a few times a week and family play days monthly. Many museums throughout Europe, such as London's British Museum (with dinosaur fossils and mummies) and Paris's Museum of Modern Art (Musée d'Art Moderne de la Ville de Paris, with amazing sculptures) don't charge admission for their permanent collections. It also doesn't cost anything to see some of the touristy attractions, like the changing of the guard at Buckingham Palace or Rome's Pantheon. In between all the sightseeing, let your kid blow off some steam at one of Europe's magnificent parks. In London, The Diana, Princess of Wales Memorial Playground in Kensington Gardens features a giant wooden pirate ship, a sensory trail, and tepees; the Parc Montsouris in Paris offers a pony ride, a puppet theater, and two carousels.