It costs a flat rate of $0.18 to send an SMS from Singapore, no matter which country you're sending it to.

Please note that this is a common charge for iPhone users. Here's why:

Apple may charge you for activation requests sent to their servers (located in the UK) whenever you:

👉 Turn iMessage on or off
👉 Turn FaceTime on or off
👉 Insert or remove your SIM card (each action triggers an iMessage request)

These activation requests are sent via GlobalSMS and cost $0.18 per message. They may be sent to various UK numbers, including but not limited to:

447937985220
447937985221
447937985222
447937985223
447937985224
447937985225
447937985226
447937985227
447937985228
447937985229
447537410205
447537410225
447537410245
447537410265
447537410285

Visit the Apple support page here: https://support.apple.com/en-ph/HT201349

An IDD plan is required to make an international call from Singapore. Learn how to get an IDD plan here