Bulk SMS in New Zealand: Spam Act, Consent and Sender ID

How must the unsubscribe option work?

It must be clear, free, usable on the same channel and valid for at least 30 days. DIA's page on unsubscribing lists what makes a facility unacceptable: not readily usable, not clear and conspicuous, costing the recipient money, not available through the same method of communication, or no longer valid within 30 days of the message.

DIA also treats continued messages 5 working days after someone attempts to unsubscribe as a valid ground for complaint. Our regulation data says the same in short form: a STOP keyword and a clearly stated unsubscribe on every marketing send, honoured within 5 business days at most. Do not use that as a target. Process opt-outs immediately.

A two-way SMS set-up that receives replies on the same sender makes the opt-out simple. The definitions of opt-in and opt-out are in our glossary.

Which networks carry SMS in New Zealand?

Three mobile networks appear in our coverage data, each with a direct route:

Read delivery reports per network rather than a single blended figure. A healthy total can hide one weak network, and our guide to improving SMS delivery rates shows how to diagnose it. For a neighbouring market with a similar open-sender approach, see our bulk SMS Australia guide.

How do sender IDs work in New Zealand?

You can usually send from an alphanumeric sender ID of up to 11 characters, or from a numeric number, but New Zealand has no published sender ID registry. Our regulation data lists formats as alphanumeric where supported, or a numeric long code or short code, and records that operator requirements are confirmed during onboarding. The lead time is free-form, so we state no typical duration.

What that means for your plan:

• Choose the sender type by purpose. A brand name helps trust for alerts and promotions. A two-way number is better when you want customers to reply.
• Test on all three networks. A sender that displays your brand on one network may not on another.
• Keep names honest. Avoid names that imitate banks, government bodies or the networks. Accurate sender information is also a legal requirement.
• Use separate senders for OTPs and promotions so a marketing complaint cannot affect your login codes.

If you want us to prepare the paperwork where a network asks for it, see registrations; approval decisions stay with the networks. The sender ID checker and the New Zealand sender ID page show the current position, and our guide to sender ID types explains the options.

How should you separate OTP and promotional traffic?

Keep OTPs, order alerts and other service messages on their own sender and route, and promotions on another. A promotion inside an OTP puts your login codes at risk if the route is filtered.

For OTP design and security, read our OTP authentication messages guide and the article on SMS pumping fraud prevention.

How do macrons and Māori words affect SMS length?

Plain English fits the default GSM 7-bit alphabet, so one message holds 160 characters (153 per part when split). Te reo Māori uses macrons (ā, ē, ī, ō, ū), which are outside that alphabet, so one macron switches the whole message to Unicode with 70 characters (67 per part). Emoji and curly quotation marks do the same. See GSM-7, Unicode SMS and concatenated SMS for definitions.

These examples were counted against the limits (Kiwi Brew is a synthetic cafe chain):

The last two rows differ by one letter. If macrons matter to your brand, accept Unicode for those messages and keep them short, or write place names without macrons only where that is acceptable to your audience. Check final copy in the SMS character counter. For other scripts see SMS character limits and Unicode.

When should you send?

We have not found a regulator-published time-of-day window for promotional SMS in New Zealand, and our regulation data records none. Agree sending hours with your provider, schedule promotions for local daytime and avoid late evenings. New Zealand observes daylight saving, so schedule against local time, not a fixed UTC offset. OTPs and alerts can go at any hour. The send time planner helps schedule campaigns, and SMS marketing rules by country compares hours across markets.

A worked example: a Wellington cafe chain

"Kiwi Brew" (synthetic) has 12 cafes and wants a loyalty-app OTP, pickup alerts and a weekly offer.

• It sets up two senders, one for transactional texts and one for promotions, and tests both on One NZ, Spark and 2degrees.
• It collects express opt-in in the app and at the counter, storing the wording, timestamp and number, and shows "Offers by text" with a clear opt-out.
• It writes OTPs and pickup alerts in plain English at 160 characters or fewer.
• Each offer starts with the trading name, ends with "Reply STOP to opt out" and is checked against the suppression list before scheduling.
• It sends the offer without macrons or emoji where a single part matters, and accepts two parts for the occasional te reo announcement.
• STOP replies feed one suppression list that also covers WhatsApp and email.

What are the common mistakes?

• Relying on inferred consent for old lists. A purchase three years ago may not support a promotion today.
• No consent evidence. The sender must be able to prove consent, so a missing timestamp is a real risk.
• Hard-to-use opt-outs. An unsubscribe that costs money or sits behind a login does not meet DIA's guidance.
• Missing sender identification. Texts that never say who is sending are non-compliant and look like scams.
• One macron in every message. It turns 160 characters into 70 and can double your parts.
• Mixing OTP and promotion on one sender.

How OmniChannels.ai helps

OmniChannels.ai is powered by BroadNet, which has direct routes to One NZ, Spark and 2degrees in our coverage data. We help you choose and test sender types, give you per-network delivery reports and support Unicode text, with SMPP 3.4 for high volume. For indicative list prices, see the New Zealand SMS pricing page, then book a demo. Small team? Our SMS marketing guide for small businesses covers the basics.