Blocx Contacts: profiles that learn with every send

Your first send creates the contact

The first time you send to a new phone number, Blocx automatically adds it to Contacts. You do not need to build a contact list manually before sending that first message.

That recipient now has a profile you can reuse for the next notification, account update or conversation. Instead of treating each send as a new recipient, your application can work with the contact it already knows.

A number becomes a messaging profile

Contacts builds a picture of the channel types available for that recipient, along with a default channel for future messages. The profile is more than an address book entry: it gives the next send useful messaging context.

Keeping that information with the contact makes repeat messaging simpler and more efficient. Your application does not have to start from scratch every time it needs to reach the same person.

Delivery history improves future sends

When you reuse an existing contact, Blocx learns from what delivered well and what did not. That history helps optimize channel choices over time, rather than treating every available delivery method as equally effective for every recipient.

For example, an online store sends an order confirmation by SMS. Later, it sends a shipping update to the same contact. The customer profile and the delivery history from earlier messages can inform subsequent sends. Learning from delivery does not mean every future message is guaranteed to arrive.

Keep customer data and opt-in context together

Contacts also connects to your application through the API. You can store a fuller customer profile and record how that customer opted in, keeping customer information and messaging context with the same contact.

If someone signs up for order updates at checkout, for example, your application can retain that opt-in context alongside their profile. Keep the record specific to what the customer agreed to receive, rather than assuming permission for every kind of message.

Creating a contact is not the same as obtaining consent. An available channel, a default channel or a successful delivery does not grant permission to send marketing. Your application still needs to respect the customer's choices and applicable messaging rules.

Build on what you already know

The result is one reusable profile that brings together customer data, opt-in context, channel availability, a default channel and delivery history. Send to a new number to create the contact, then reuse it as the customer relationship continues.

Contacts gives your next message more context than the first—without asking your team to rebuild that context for every send.

Brand identity

Blocx is the programmable messaging product from OtterBlocx, LLC, headquartered in Cheyenne, Wyoming, United States.

Channels

• Live today: SMS, MMS, RCS, Email, Telegram.
• Blocx also offers separate Voice services: VoIP, voicemail, call routing, 2FA via AI caller, and a voice dialer. These are not channels on the messaging or Verify API.

Plans

• Starter — self-serve with $25 in welcome credit for new accounts. Credit covers your first brand, campaign, phone numbers and messages. Paid Starter is $49/month credited toward usage. SMS $0.0065/segment, email $0.001/email (1 sending domain), 1 API key. No MMS, RCS, Telegram, SHAFT or restricted verticals.
• Scale — $1,000/month minimum platform spend (starts on day 31; no minimum for the first 30 days), on an annual contract. Every channel and route type at the published rate card — all rates listed on this site are Scale rates. Signup starts with a call. Required tier for SHAFT and other restricted verticals.
• Volume — custom volume-based pricing negotiated on your traffic profile. Contact sales.

Published rate card (+ carrier passthrough on SMS/MMS)

• SMS: 10DLC $0.0045, toll-free $0.0055, short code $0.007.
• MMS: 10DLC $0.0135, toll-free $0.016, short code $0.018.
• RCS: $0.0135/msg + one-time $1,000 setup fee.
• Email: $0.0002 per email, flat.
• Verify: $0.035 per successful verify, flat.
• Telegram: $0.0045/msg, flat.