Please be aware that Rome has multiple airports and that these results are for all airports serving the city.
The best month to arrive at Rome is January and the most expensive month to fly is April. (Average prices, based on 700 datapoints.)
The best day to arrive at Rome is Wednesday and it would be best to avoid Saturday, as prices are on average 46.88% higher than on Wednesday. (Average prices, based on 720 datapoints.)
The cheapest airline flying to Rome is Vueling. They are 79% cheaper than Lufthansa. (Average prices, based on 775 datapoints.)
From Rome it is on average the cheapest to fly to Madrid and to Brussels. (Average prices, based on 154 datapoints.)