Best Winter Month to Travel in Italy

I've been to northern Italy many times from mid December to early February and always found the temperatures mild, with no snow (except in the Alps). But if you go in March, you will get much more day light.

If it were my trip, and Jan-Mar is the only time window, I'd go as late as possible in March.

I agree with the others. I spent about a month in the Rome/Naples area this year, beginning in mid-February. The short days bugged me, and they are absolutely 100% guaranteed to occur. Temperatures can vary, of course. I was lucky in that I don't think I had any days colder than the historic average. However, there was a persistent pattern in February of not seeing 40 F until close to noon, so the mornings were very chilly and I (cold-natured) needed to start out with all my layers. Toward the end of the trip it seemed to warm up a bit earlier, and the extended daylight made the late afternoons seem warmer, too. I had a reason (Schengen 90-day limit) for scheduling my trip as early as I did, but I'd have been a lot happier with a March/April trip--or April/May.

However, Easter falls on March 31 next year, and I'd expect a considerable bump in tourist traffic beginning the week before Easter, just based on comments I've read here over the years. Lodging prices will most likely follow the same pattern as the crowds. I suspect it would help to organize your itinerary so you avoid the busiest places (Rome, Florence, Venice) the week before Easter. Timing of spring break in the countries feeding the most travelers to Italy will probanly also be a factor. You may be able to get some information on that by Googling.