Unlimited Minutes and SMS'

You acknowledge and accept, for the voice & SMS' allocated with the Plan(s) that the unlimited minutes and SMS' applies to:
Domestic mobile ON-net usage (Maxis to Maxis calls and SMS’) for MaxisONE plan lite & start (excluding OFF-net usage (calls and SMS’ from Maxis to other Service Provider), calls to fixed lines, video calls, calls to numbers with special charges e.g. 1-300/1-700/600 & 121, TM100, 1MOCC, 02-prefix numbers for IDD calls to Singapore and 080-prefix numbers for border calls to Brunei).
Domestic mobile/fixed ON-net & OFF-net usage for MaxisONE plan 98, 128, 158 & 188 (excluding, video calls, calls to numbers with special charges e.g. 1-300/1-700/600, 121, TM100, 1MOCC, 02-prefix numbers for IDD calls to Singapore & 080-prefix numbers for border calls to Brunei).
standard person-to-person calls or texts and not for any commercial and/ or non-personal usage;
non multiple simultaneous calling, conference calling (unless you are subscribed to the conference calling service with Maxis), re-supply, call centre usage, telemarketing, bulk messaging, application-to-person communication, continuously call forwarding, auto-dialing, machine-to-machine communication (including by using your SIM card in any other devices), Cellular Trunking Units (CTUs), or any other activity we consider to be non-standard usage.

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suppose yes, because 1800 are free phone numbers.