You can send an SMS to a Simbase SIM from two places: the dashboard or the API. Replies from the device appear in both, and can also be pushed to your own endpoint with a webhook that fires on each incoming message.
What a SIM can exchange SMS with depends on its profile. Some ship without a public phone number and talk only to the Simbase shortcode; others ship with a 15-digit IoT MSISDN that external numbers can usually reach. The dashboard, API, and webhook mechanics are identical across profiles.
Black profile
This profile does not come with an MSISDN (a public phone number) assigned. SMS is limited to the Simbase shortcode:
Inbound: the SIM can receive SMS from Simbase's shortcode +55555, which is what the dashboard, API, and your webhooks use. SMS from any other phone number won't reach the SIM.
Outbound: the device can send SMS to +55555 only. Outbound SMS to any other phone number is blocked.
Every SMS to or from these SIMs is visible in the dashboard, and can be relayed through a webhook or read from the API.
If you need a real MSISDN on a Black, Red, or Green SIM (so external numbers can SMS the device or so the device can SMS external numbers), MSISDNs are available only for orders of 100 or more SIMs, at an additional cost. Contact sales for terms.
Send an SMS from the dashboard
Send one SMS at a time (with optional reply tracking), or send the same SMS to many SIMs at once.
Send a single SMS
If you want to see replies from the device, use this flow:
Sign in to dashboard.simbase.com.
Open SIM cards and click the SIM you want to message.
Open the SMS tab. An inbox view appears.
Type your message and click the envelope icon to send.
The sent SMS appears in the inbox. Replies from the device land here too.
Send the same SMS to many SIMs
Open the SIM overview page.
Use filters, tags, or search to narrow the list to the SIMs you want.
Select the SIMs (checkbox).
In the action bar, click Send SMS.
Optionally deselect any SIM you don't want included.
Type the message and click Send.
All selected SIMs receive the same message simultaneously. Useful for commanding a fleet ("reboot", "report status", and so on). See Tags for how to scope a bulk SMS by tag.
Receive SMS via webhook
If you want to react to incoming SMS programmatically (forward to Slack, log to a database, trigger an automation):
Set up a webhook endpoint for SMS messages in Integrations → Webhooks in the dashboard.
When Simbase receives an SMS from your device, it POSTs to your endpoint immediately.
Your endpoint receives the message payload.
See Webhooks for the full payload format and configuration steps.
Send and read SMS via API
The Simbase API supports both sending SMS to SIMs (Simbase shortcode delivery) and reading SMS that have been sent from your devices to the Simbase server.
See the API documentation for endpoints, parameters, and examples.
Common questions
No. Black, Green, and Red SIMs have no MSISDN, so they exchange SMS only with the Simbase shortcode +55555. Messages from any other number won't reach the device. If you need a reachable number, MSISDNs can be added on orders of 100 SIMs or more. Contact sales for terms.
Outbound SMS from Black, Green, and Red SIMs is restricted to +55555; anything addressed elsewhere is blocked. To get device messages out to a person or system, read them in the dashboard or receive them via webhook and forward from there.
No platform-level limit. Very large blasts may hit destination-network rate limits. If you're sending to thousands of SIMs at once, consider batching.
Related
Webhooks, receive incoming SMS via HTTP
API, programmatic SMS send/receive
Tags, scope bulk SMS by tag
SIM Profiles, full profile breakdown
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