How long will it take to get from the UK to Australia on a boat?
40 days approx
The distance from London, UK to Perth, Australia is 7,823 nautical miles. if your boat sails at 20 mph, it would take 16 (24 hour) days 7 hours and 12 minutes to get there. At 30 mph, it would take 10 days 20 hours and 36 minutes. At 40 mph, it would take 8 days 3 hours and 18 minutes. Basically, the faster you sail, the less time your trip will take.
It depends if you prefer by air, road or sea. There is a company I use that has a Parcel Forwarding service and ships from UK to Australia. http://www.mailboxuk.com/ParcelsForwarding.asp To find out how long it takes try this: Just put in the destination country as Australia then press get quote, it should show you how many days it takes from UK to Australia on the default parcel settings. :-)
In 1975, it took 5 weeks to do the trip in the opposite direction, i.e. Sydney to Southampton, UK; It probably has not changed much since then. It took 6 weeks in 1966 to come through the Panama Canal via Tahiti and New Zealand, but faster ships were doing the voyage through the Suez Canal to Australia in about 4 weeks.