Sending International SMS or Text message from Australia..
To send a message to an International number you need to +CountryCode before the number, and remove the leading zero.
eg: Using the Mobile number of 0414 141 414
0414141414 would need to be entered as ‘+441414141414’ using the country code of +44 for UK
or:
0414141414 would need to be entered as ‘+631414141414’ using the country code of 63 for the Philippines
The + sign is important
Cost of Sending International SMS or Text message from Australia
Prices as at January 2015
Optus:
How much does it cost to send an international SMS?
For Postpaid Mobile, international SMS is charged as per your rate plan per message sent up to 160 characters.
For Prepaid Mobile, international SMS is charged at $0.35 per message sent up to 160 characters (excludes Connect 4 Less)
http://www.optus.com.au/shop/mobilephones/internationalcallingrates/sms
Vodafone:
What it costs
On most plans and prepaid recharges, international TXT sent from Australia are charged at the same rate as standard TXT.
You can check your plan details in My Vodafone.
365 Day Plan costs 28c per International TXT (Up to 160 characters) (5c per TXT delivery notification message)
TXT sent while international roaming are charged as roaming TXT.
http://support.vodafone.com.au/articles/FAQ/Sending-and-receiving-international-TXT-messages
Telstra:
Costs
$0.50 per Text (SMS) per recipient to any standard international number
https://www.telstra.com.au/mobile-phones/plans-and-rates/calling-overseas-from-australia
41.1 - 873,806