Overview

The API supports two-way messaging, inbound webhooks, SMS, MMS, and sender options spanning 10DLC, short codes, toll-free numbers, alphanumeric IDs, and global mobile numbers. Bandwidth says these options reach more than 120 countries. That range gives teams room to choose routes for different needs, but it also makes channel selection part of cost planning rather than a set-and-forget decision.

Registration Center can autofill customer and campaign data across Short Code and 10DLC channels. Traffic monitoring identifies unregistered traffic and messages blocked by carriers or Bandwidth, with alerts by email or webhook. Those tools help teams find registration and delivery problems; they do not replace the operational work of investigating them.

Key features

New accounts start with a default outbound rate limit of one message per second for testing. A2P traffic can reach the account limit, so teams planning production throughput need to account for the limit attached to their account rather than assume the testing rate represents production capacity.

If an inbound webhook endpoint does not return HTTP 2xx, Bandwidth retries delivery multiple times over the next 24 hours and then stops. This gives receiving systems a recovery window, but teams should handle events idempotently and monitor failed deliveries so events are not missed after retries end.

Bandwidth says it does not retain message text, keeping metadata for message queries after successful webhook delivery. Data is encrypted in transit and at rest using protocols including TLS, SIPS, and SRTP. The company lists SOC 2 Type II compliance and says eligible services meet HIPAA security requirements; teams should confirm service eligibility against their own compliance needs.

Developer documentation includes integration guides for ServiceNow, Zendesk, and Salesforce. Messaging customers receive Signature support, with Premium packages available for on-call, ongoing assistance. That can suit teams that need escalation options, though Premium support is an additional choice rather than the default support arrangement.

Pricing

Pricing is paid and available on request, with a free trial and no free plan. The published U.S. outbound message rates are billed per message:

10DLC SMS: 0.00 USD per message.
Short code SMS: 0.01 USD per message.
Toll-free SMS: 0.01 USD per message.
10DLC MMS: 0.02 USD per message.
Short code MMS: 0.02 USD per message.
Toll-free MMS: 0.02 USD per message.

The 10DLC SMS rate is the lowest listed U.S. outbound option, while short-code and toll-free SMS cost more per message and all three MMS routes carry a higher rate. These figures make route and format choices material at volume. The account-level pricing on request means teams should confirm their full expected charges before committing; the free trial provides a way to evaluate the service, but there is no ongoing free tier.

Platforms

The API is available through API and web platforms. SDK languages include Node.js, Python, Java, C#, PHP, and Ruby, giving teams several common server-side integration options.

Who it's for

Bandwidth fits companies that have outgrown a single-provider messaging setup and need multiple SMS and MMS routes, two-way exchange, monitoring, and room for higher A2P throughput. It is less suitable for teams that require an always-free plan, need a high initial testing rate, or want a single universal message price.

Pros and cons

Pros: Multiple U.S. route and message-type options, plus messaging reach across 120+ countries, give teams flexibility as their deployment expands.
Pros: Registration autofill, traffic monitoring, and email or webhook alerts provide useful operational visibility for teams handling campaign setup and delivery issues.
Pros: Webhook retries, message-text non-retention after successful delivery, encryption, and stated compliance credentials support operational and security planning.
Cons: New accounts default to one outbound message per second for testing, which is a constraint for teams validating high-volume behavior before account limits are established.
Cons: Route and format charges vary, and overall pricing is on request, so teams must map anticipated traffic to routes and confirm the full cost.
Cons: There is no free plan, making the trial the only stated no-cost evaluation route.

Alternatives

Consider Gupshup if a free plan and messaging-focused API matter; its listed messaging fee is 0.001 USD per message, with WhatsApp fees billed at actuals. Telnyx Text-to-Speech API is an option for buyers who want a free plan and pay-as-you-go pricing with no contract, though it is a text-to-speech API rather than a like-for-like messaging choice. EnableX Video API suits teams seeking a video API with a free trial and per-participant, per-minute pricing. Infobip Voice API is an alternative for teams evaluating voice capabilities and voice add-ons. Orbit by Devotel offers a freemium, self-hosted option with two team members included. Airtel IQ, Comviva API Marketplace, and Telesign Communications Platform are additional paid platform options.

Browse Communications Platforms as a Service, Transactional SMS Software, RCS Messaging Platforms, RCS Business Messaging Software, and SIP Trunking Providers to compare adjacent categories.

Verdict

Choose Bandwidth Messaging API if your team needs configurable SMS and MMS routes, global reach, and monitoring as messaging volume grows. Its strongest case is the combination of route choice and operational tooling; look elsewhere if a free tier, straightforward pricing, or a higher default testing rate is essential.

	Bandwidth Messaging API	Callr
Free plan	No	No
Free trial	Yes	No
Paid from	—	€599/mo
Open source	No	No
Platforms	api, Web	Web
Free plan	No	No
Pay-as-you-go	Yes	—
SMS API	Yes	—
Delivery status	Yes	—
Webhooks	Yes	—
Two-way messaging	Yes	—

Bandwidth Messaging API vs Callr

Bandwidth Messaging API

Callr