How much is a ticket from Rome to Cagliari?

The cheapest price found today is $21.

When is it cheaper to fly?

Cheapest month is September — from $21.

Cheapest today — $21. Below is what booking services offer.

Departure	Airline	Stops	Price
Sep 15	Ryanair	direct	$21	View
Sep 1	Malta Air	direct	$21	View
Sep 20	Malta Air	direct	$21	View
Sep 28	Ryanair	direct	$22	View
Sep 6	Malta Air	direct	$22	View
Sep 8	Malta Air	direct	$22	View
Sep 14	Malta Air	direct	$22	View
Sep 17	Malta Air	direct	$22	View
Sep 19	Malta Air	direct	$22	View
Sep 21	Malta Air	direct	$22	View

How much is a ticket from Rome to Cagliari?: The cheapest price found today is $21.
When is it cheaper to fly?: Cheapest month is September — from $21.

Links to booking services are affiliate links. The price stays the same for you.