If you don’t have time, just search for your departure airport to Kahului (OGG).
If you have time to piece together your route, make stopovers to sight see, then you can try several things.
To get to Maui, you can fly to Honolulu (airport symbol HNL) and then catch a short 30-minute flight to Kahului (airport symbol OGG). There are direct, nonstop flights to Kahului from mainland USA but they are probably the most expensive. The return flights between Honolulu and Kahului range from $135 to average of $160, at time of writing. There are many per day and easy to book at last minute.
To save money, look for the cheapest ticket from your departure city to Honolulu (HNL). Another method is to look for the cheapest ticket to west coast USA or any of the major airline hubs and grab a special offer from Hawaiian Airlines, Alaskan Airlines, or others you can find through the multi-fare search engine kayak.com.
Airfares in the USA are very competitive. It’s not necessary to buy round-trip tickets, though they are slightly cheaper than two one-way tickets. One way and multi-city bookings are possible. Of course, round trip (A to B and B to A) and multi-city return (A to B and return from C back to A) tickets are less expensive than one way tickets bought at different times.
What adds to the fares are checked-in baggage charges. A multi-stop flight where you can check your bags from origin to final destination won’t accrue separate baggage charges if you don’t go through baggage claim. Southwest Airlines is one of the few that do not charge for checking in bags, at least the first 2 per passenger. These check-in luggage charges are waived for international travel, e.g. London to Kahului (with stops but not stopovers).
Off-peak fares are considerably lower than peak fares (such as summer and public holidays). The earlier you book, the more available are the lower priced fares. The early bird catches the worm. I typically spend a bit of time trying different fare search engines, doing sensitivity analysis on the dates and routing, until I am ready to book.
Sometimes it’s cheaper to fly from London than from Amsterdam. On expedia.nl, I found Amsterdam (AMS) to Kahului (OGG) in February 2011 — cheapest euro 930 for a return ticket. If you have a thousand euros to spare and time to get away, you can afford this trip to paradise.
Continental Airlines boasts the cheapest fares from Europe to the USA. The good news of their merger with United Airlines is that there are more flights that are more affordable. A quick search on opodo.co.uk produces a round-trip ticket from London Heathrow (LHR) to Kahului (OGG) in February 2011 for a mere STG 600.
Airmiles work the same way. The earlier you book, the more flights are available for airmiles.
cheaper fares: more stops and change of planes (but not stopovers), off-peak season, piece together special offers, avoid Friday travel