40th Anniversary Trip to Italy

Couple things...

Adding in London does complicate things a bit, but not much. Given the choice between doing London on the way over, or on the way back, my preference would be to do it on the way, and fly home from Italy. For two reasons...

1. The UK (and London) has some of the highest fees/taxes on departing from there. You will save a few bucks if you fly in to London rather than flying home from there. Not a ton of money, but all things being equal, saves you a few.

2. Culturally, Italy will be more "intense" than London. London will be "easier", more familiar, less "spicy". So do that first, to ease into your trip, then after you have your "sea legs" a bit, proceed to Italy with all its thrills.

Hope that helps. Have a great trip.

Don’t rent a car in Italy and I know you will be tempted because the upfront cost is so cheap. They have a year to issue you tickets and we got that international license, read up on travel zones, speeds, travel signs. The, hopefully only, ticket came in yesterday for a journey two months ago. It was 10 minutes into our drive for being in a bus lane? I am terrified now because we don’t recall even doing anything wrong. Don’t know how many more are coming.... don’t drive. Take the trains and get a driver. We only drove 3 of our 11 days because we went to Perugia and Assisi. Those towns have hours you are allowed to drive in the city and we stayed in those hours but by the grace of God. I guess we will just keep our fingers crossed at this point. Take trains and just make sure you get them stamped, or pay and get a driver. They are not much more from the ones we got.

Fly SEA -> FCO and then LON -> SEA as one complete multileg trip. It’s quite common and easy to do.

Rick Steves has good article on flights: https://www.ricksteves.com/travel-tips/transportation/budget-flights

Plus, consider trains within Europe when possible. Lastly, add day trip to visit town of Lucca if possible when in the Tuscany region.

Happy 40th! And congrats too!

Fly SEA -> FCO and then LON -> SEA as one complete multileg trip

Or the opposite- SEA to FCO-- then LON to SEA based on what David posted- good advice about getting acclimated in London before going to Italy.

Then a cheap intra Europe flight from London to Florence or Venice- depending on how your itinerary works out- figure that bit out first!
Check RyanAir or EasyJets

The best airline depends on what is available to you in Seattle, price, flight times etc.
Book flights with the actual airline- not Kayaklor Expedida, etc.

And Happy 40th! We just spent our 40th in Italy as well

I can only tell you how my wife and I have started doing our own trips - in our case from Denver though the basic principle would apply to a flight from Seattle as well.
Basically, we book R/T flights to London, spend a night or two there to recharge our batteries (acclimate to the time change, recover any lost sleep from the flight over by sleeping in a real bed, etc.) then use one of the low-cost airlines to proceed on to our final destination ... refreshed and ready to go. Since there's no penalty for one-way flights on the discount carriers we book those to/from London ... in our particular case last May it was into Pisa and back to London from Florence. Worked great for us since we're at an age where we like to take it slow and easy, ie not wear ourselves out in order to maximize the chances of staying healthy for the duration of the trip.
Turns out that it's also cheaper for us to fly the R/T to London rather than trying to make it all the way to Italy in one go, which we find to be overly tiring once we factor in the required stopover.
There's a Premier Inn at Terminal 4 at Heathrow that's quite nice, is convenient to the other terminals for ongoing flights to Italy (or elsewhere), and at less than USD$60 per night you can't beat the price.

You don't mention the length of your trip. Perhaps you haven't made a decision about that. My #1 tip is to make the trip as long as you can. As you continue planning the trip, you will learn about many things that interest you: Perhaps the Imperial War Museum in London and the Bletchley Park code-breaking site that's a day-trip away? And then there's Italy. What you've laid out for Italy so far really needs more than the classic "2 week" trip (which usually means just 13 nights on the ground in Europe). More time will allow you not to end up rushing from place to place.

To find flights into England and out of Italy, or the reverse, choose "Multi-city" on your flight website of choice. I use Google Flights for transatlantic flights and skyscanner for intra-European flights. Don't try to include the hop between England and Italy several days later on the same ticket as the transatlantic flight; that will cost you more.

I, myself, would not choose to fly round-trip to London and spend time there at both ends of the trip unless I had a great deal of time. Trekking out to the airport eats up a lot of time and can cost a fair amount of money. No way I'd want to do it four times when three would be sufficient for a trip to just two countries.

I heartily second the recommendation for the bargain-priced Premier Inn at Heathrow Terminal 4 should you need a hotel at that airport.

"would not choose to fly round-trip to London and spend time there at both ends of the trip".
Actually, we wouldn't do it that way either. We only venture into London at the beginning of the trip if we plan to delay a few days anyway, and if we do using the Heathrow Express is a pretty efficient way to do it - not a lot of wasted effort at any rate. On our most recent trip in May we just stayed overnight at the Premier Inn and headed to Pisa the next morning - much more restful for us to do it that way.
On our return we fly into Heathrow the evening before our return flight to the US and check into the airport hotel so we're in place for a reasonably stress-free and rested travel day to follow. We don't go into London on the return for exactly the reason you state.

Thank you everyone!! Read through and considered each reply with my husband as we continued researching our trip.
Decided on spending the extra $$ to meet with consultant at Rick Steves offices and while it may have been quite a bit
of money, it put our minds at rest about where to fly into, airline, places to visit, lodging, itinerary, etc. Pat was really helpful
in this area and even suggested a tour at the Sistine Chapel through Walks of Italy!

Also another wonderful lady there suggested we fly into Amsterdam instead of Paris CDG as customs/immigration lines can
be really long waits plus considering our short stopover wouldn't want to miss connectingn flight. We got our tickets!! Flying to Rome from Seattle via Amsterdam then from London to Seattle. Taking another flight from Florence or Milan to London to spend 4 nights there.
Again, thank you so much!!
Anna