I have no clue why I never did this, but there's a cost effective way to send/receive texts even though you're out of the country.
I know what I'm suggesting seems obvious, but I never did it despite 7+ trips to the country until one of my dates suggested it...
1. Set up international roaming
Before you leave the country, set your number for international roaming. You want to do it just before leaving because activating roaming involves texting something to the provider. Obviously, you can't text your request once you're out of the country.
Setting up roaming on Smart:
Setting up roaming on Globe:
Setting up roaming on SUN:
2. Set up Skype
OK, once you're on roaming, you'll get texts from the Philippines and it won't cost you anything as long as you maintain a specific load amount (usually P100) and that the load hasn't expired.
But to reply, it costs P20-P25 depending on the service provider. This gets pretty hefty.
A more cost effective way to reply is through Skype. On Skype, texting to the Philippines is P3 each. And you can set up caller ID on Skype so that, when your friend gets the text, it looks like it came from your phone.
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If you're no longer in the country but still have your SIM, you can also set up international roaming from abroad on Smart. It's done through their website. But you have to have at least P100 left on your load to activiate.
If you don't have a P100 load, you can buy this load from abroad. Just Google "buy load Philippines" and you'll find several providers.
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If you're out of the country and don't have your SIM card, you can buy one on Ebay that already has international roaming set up. It's then just a matter of plugging that SIM into any unlocked phone and you can text to the Philippines as if you're there.