Sinch SMS API review

by SinchSMS and messaging APIs

A prepaid SMS API with a published US rate of $0.0078 per message, a price list for 241 countries and 10DLC registration from the dashboard or the API.

Facts checked2026-10-15

Free trial
No card needed
Self-serve
Usage-based
Public prices

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What you're paying for

Built-in reach (main value)
Compliance included
Saves engineering time

Prepaid SMS priced for 241 countries from one account, with US 10DLC registration in the same dashboard or API and a SOC 2 Type II that names the SMS API.

Sinch, which says it has 600+ direct carrier connections, sells SMS from one prepaid Sinch Build account, with prices for 241 countries on its pricing page and the same $0.0078 per US message on 10DLC and toll-free numbers. US registration stays in the same place: 10DLC brands and campaigns can be registered in the dashboard or through an API, and existing TCR records transfer in. The trust center lists a SOC 2 Type II for the SMS API and a group ISO 27001 certificate, the DPA is part of the online terms, and the SMS API has servers in the EU, Australia, Brazil and Canada.

One price list for 241 countriesThe SMS pricing page has a country selector built from 241 countries, with a fixed US block: $0.0078 per 10DLC or toll-free SMS and $0.009 on a short code.Evidence: SMS pricing page (2026-10-15)
SOC 2 Type II that names the SMS APIThe trust center announces a SOC 2 Type II for "Sinch Messaging API - SMS" and lists a group ISO 27001 certificate; the DPA is incorporated into the online Terms of Service.Evidence: Trust center, Terms of Service and DPA (2026-10-15)
10DLC registration by APIThe 10DLC Brand and Campaign Registration API creates brands and submits campaigns, with a downloadable OpenAPI file; the dashboard does the same and imports existing TCR records.Evidence: 10DLC Registration docs and Sinch Build page (2026-10-15)
Test without sendingThe texting sandbox simulates and logs messages without sending real ones, and the batches dry-run endpoint calculates message parts at no cost.Evidence: Testing sandbox page and SMS batches docs (2026-10-15)

Best for: Teams that send SMS in many countries from one prepaid account and want SAML SSO, data regions outside the US and a SOC 2 Type II for SMS.
Good to know: US carrier and 10DLC fees sit in community help articles rather than on the pricing page, and those articles say their prices are "only indications".

How Sinch SMS API compares

Against 3 other products we reviewed in SMS and messaging APIs: what you pay for with each, the five access facts, the plan limits we recorded and each review's bottom line. The note under the table says how each one was checked.

Sinch SMS API compared with Telnyx Messaging API, Twilio Programmable Messaging, AWS End User Messaging SMS
Metric	Sinch SMS API	Telnyx Messaging API	Twilio Programmable Messaging	AWS End User Messaging SMS
What you're paying for	Built-in reachPrepaid SMS priced for 241 countries from one account, with US 10DLC registration in the same dashboard or API and a SOC 2 Type II that names the SMS API.	Worth the priceUS texting at $0.004 a part, the lowest published rate in this group, with carrier and 10DLC fees passed through at cost and every messaging rate public.	Compliance includedUS texting with every fee and the compliance paperwork on public pages, plus opt-outs and 10DLC registration handled through the API.	Compliance includedUS texting from your own AWS account, inside AWS’s SOC 2, ISO 27001 and HIPAA scope, with opt-outs, events and 10DLC registration as AWS APIs.
Overall score	7.6	8.2Best	7.2	6.9
Free option	Free trial	Free trial	30-day free trial	Paid only
Card to start	No card needed	No card needed	No card needed	–Not measured
Getting access	Self-serve	Self-serve	Self-serve	Approval wait
Starter priceCheapest paid plan	$0.0078/message	$0.004/SMS part	$0.0083/SMS segment	$0.00774/US SMS + carrier fee
Pricing model	Usage-based	Usage-based	Usage-based	Usage-based
Pricing page	Public prices	Public prices	Public prices	Public prices
US SMS rate (10DLC)	$0.0078 per message, outbound or inbound	$0.004 per part, outbound or inbound	$0.0083 per segment, outbound or inbound	$0.00774 per message part, outbound; inbound $0.0075
US carrier fees	Per carrier: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.0050 (outbound; carrier fee article of Oct 1, 2026)	Per carrier, no markup: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.0045 (outbound)	Per carrier: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.005 (outbound)	One all-network fee: $0.00421 (10DLC, long code, toll-free)
Local number	$1.00/mo plus $1.00 setup	$1.00/mo plus $0.10/mo for SMS and MMS	$1.15/mo	$1/mo (10DLC)
10DLC registration fees	Brand $4, campaign review $15 per submission, $10/mo standard or $1.50/mo low-volume mixed (under 10k SMS/mo); optional vetting $41.50	Passed through: brand $4.50, campaign review $15, $1.50/mo low-volume mixed	Passed through: brand $4.50, campaign vetting $15, $1.50/mo low-volume mixed	Brand $4.50, optional brand vetting $41.50, campaign $2/mo low-volume or $10/mo; no campaign vetting fee listed
Reference scenario (10,000 US texts/mo)	$134.00, computed	$85.89, computed	$130.61, computed	$122.88, computed
Free option	Trial credit, no card ($2 for US accounts per archived help); texting sandbox	$5 testing credit after a fraud review, no card; texts only to your own verified number	30-day trial: 100 SMS to up to 5 verified numbers, no card	None for SMS; sandbox sends billed texts to up to 10 verified numbers
Volume discounts	Not published; contact sales	Published tiers, from 100M parts/mo on local numbers	Mentioned but not published; committed use by sales	None listed for SMS
SOC 2 / ISO 27001	SOC 2 Type II naming the SMS API; group ISO 27001 certificate	SOC 2 Type 1 and Type 2; ISO 27001:2013 (scope not stated)	SOC 2 Type 2 (all services) and ISO 27001	Listed in AWS SOC 1/2/3 and ISO 27001 scope
HIPAA BAA	Product-level BAAs offered; SMS API not named	Yes, US messaging traffic only; rate sheet lists $2,500/mo	Yes, SMS eligible; needs Security or Enterprise Edition	HIPAA eligible under the AWS BAA (voice and WhatsApp excluded)
Non-US data region	EU (Ireland, Sweden), Australia, Brazil, Canada through the account manager	EU (Germany), Australia, UAE or Canada, chosen once	Ireland (IE1) for SMS; no +1 numbers there	The AWS Region you pick, EU Regions included
Opt-out handling	Automatic STOP blocking once consent management is switched on (Conversation API)	Automatic STOP and similar keywords; AI detection $0.002 per message	Automatic STOP/HELP on long code and toll-free	Automatic STOP/HELP by default; self-managed optional
SSO	SAML in Sinch Build; no plan condition stated	SAML through Organizations; no plan gate stated	SAML 2.0 in Twilio Editions, by sales	SAML 2.0 through IAM Identity Center, no extra charge
Bottom line	From its public pages, Sinch offers a prepaid SMS API with per-country prices, SAML SSO, non-US servers and a SOC 2 Type II for SMS. Its US carrier and 10DLC fees sit in help articles that call them "only indications".	From its public pages, Telnyx has the lowest published US rate and scenario figure in this group, with every fee itemized and passed through at cost. US 10DLC needs the Verified tier with KYC, the trial is narrow, and several pages disagree on fees and plans.	From its public pages, Twilio publishes every US fee and a full set of compliance documents for SMS, with opt-outs and 10DLC registration handled by the platform. Our scenario costs more than at Telnyx or AWS, volume tiers are not published, and a few pages disagree on fees.	From its public pages, AWS End User Messaging SMS pairs a published US price with AWS’s compliance scope, and SSO and an audit log at no extra charge. There is no trial, production needs approval per Region, and technical support is a paid plan.

Evidence: Sinch SMS API: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; Telnyx Messaging API: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; Twilio Programmable Messaging: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run; AWS End User Messaging SMS: facts checked 2026-10-15 from its public sign-up and pricing pages, no completed hands-on run. Prices in USD as listed, excluding tax. "–" means not recorded.

Compare side by side All SMS and messaging APIs

Overall score7.6/10Good

Score breakdown

Pricing clarity: 7.0 / 10, Good; carrier fees per carrier; 10DLC fees published; no published volume tiers; per-country prices; pay online; minimum top-up stated in euros only; trial credit amount not stated on the live pages ($2 only in archived help articles)
Free trial: 7.6 / 10, Good; trial credit $2, no card needed, test credentials or sandbox
Price for 10,000 US texts: 5.7 / 10, Fair; $134/mo: 10,000 × $0.0078 = $78.00 (10DLC SMS rate, pricing page) + 10,000 × $0.004333 = $43.33 carrier fees (mean of AT&T $0.0035, T-Mobile $0.0045, Verizon $0.0050) + $1.00 number + $10 standard campaign (the fee article limits the $1.50 low-volume mixed campaign to under 10k SMS a month) + ($4 brand + $15 campaign review + $1 number setup) / 12 = $1.67; assumes the fees in Sinch's carrier fee article (Oct 1, 2026) and 10DLC fee article (updated Sep 17, 2026), read in the community RSS feed because the article pages returned a bot challenge, and which say prices are "only indications"; one campaign review submission; every message delivered
Compliance documents: 8.0 / 10, Excellent; own SOC 2 Type II, ISO 27001, self-serve DPA, non-US data region
Messaging features: 10.0 / 10, Excellent; delivery webhooks, inbound webhooks, automatic opt-out handling, verification API, 10DLC registration API, official SDKs
Team access and support: 7.0 / 10, Good; SSO on a self-serve plan, team roles, 2FA, no paid support plans listed, tickets for every account

Review from public pages

Written from Sinch SMS API's public pages (pricing, security or privacy, and docs) as read on Oct 15, 2026. We did not sign up, and no hands-on run is published yet.

What the public pages show

We read Sinch's SMS API product page, the SMS pricing page, the Sinch Build and texting sandbox pages, the SMS docs (API reference, webhooks, delivery reports, batches, SDKs, rate limits), the Conversation API consent management and 10DLC Registration docs, the trust center, and the Terms of Service, DPA, HIPAA and Messaging SLA pages on Oct 15, 2026; we did not sign up or call the API for this review. The help articles on community.sinch.com that the pricing page links for carrier and 10DLC fees returned a bot challenge, so we read their current text in the community's own RSS feeds; the older trial, user role and SLA articles were read from their latest Internet Archive copies, and we say so where we use them.

The pages make the base rates clear. A US SMS is $0.0078 on a 10DLC or toll-free number, sent or received, a 10DLC number is $1.00 a month plus $1.00 setup, and the country selector covers 241 countries. The carrier fee article (Oct 1, 2026) lists fees per carrier, and the 10DLC fee article (updated Sep 17, 2026) lists a $4 brand fee, a $15 campaign review fee and the full table of monthly campaign fees, with low-volume mixed limited to under 10k SMS a month; both say the prices are "only indications". The docs cover delivery and inbound webhooks, a 10DLC Registration API and SMS servers in the US, EU, Australia, Brazil and Canada.

Two things need a question. The live pages promise trial credit without naming an amount; archived help articles give $2 for US accounts. The texting sandbox is separate: its simulated messages are free and unlimited. And the HIPAA page says Sinch has product-level BAAs but does not say whether the SMS API is one of them.

Strengths

SAML SSO with no plan condition stated
The Sinch Build page lists Sinch ID SSO, SAML, 2FA with recovery codes, MFA and passkeys, with no plan condition, and projects and subprojects with scoped credentials. The archived roles article lists five user roles.
Compared: Twilio puts SAML SSO in Editions sold by sales, and Plivo offers SSO on its Enterprise plan.
SMS servers outside the US
The SMS API reference lists base URLs in the EU (Ireland, Sweden), Australia, Brazil and Canada, and says customer data is stored in the chosen location; access is set up through the account manager.
Compared: Plivo’s data regions are the US and India, and SMS is not offered in the India region.
Compliance documents for the SMS API
The trust center lists a SOC 2 Type II for "Sinch Messaging API - SMS" and a group ISO 27001 certificate, and the DPA (version 8, Oct 29, 2025) forms part of the online terms.
Compared: Telnyx and Plivo offer their DPA on request.
Trial and sandbox without a card
Sign-up gives trial credit without a card, the texting sandbox simulates messages to verified numbers, and the dry-run endpoint calculates message parts without sending or billing.
Compared: AWS has no SMS trial, and its simulator numbers bill at the standard rate.
Developer features in one place
Delivery report and inbound webhooks, a 10DLC Registration API, a separate Verification API and official SDKs for Node.js, Java, .NET and Python are all in the docs.

Things to know

Carrier and 10DLC fees off the pricing page
Every US row says "Carrier fees apply" and links to community help articles, which returned a bot challenge on Oct 15, 2026, so we read them in the community RSS feed. The carrier fee article (Oct 1, 2026) and the 10DLC fee article (Sep 17, 2026) say their prices are "only indications".
Workaround: Ask Sinch for the current carrier and 10DLC fees before committing volume.
Trial credit amount only in archived articles
The live pages promise trial credit without an amount; archived help articles give $2 for US accounts, with custom text only to up to 5 verified numbers and other messages replaced by a test template. The texting sandbox is separate: its simulated messages are free and unlimited.
Workaround: The dry-run endpoint calculates message parts without sending and costs nothing.
No BAA named for SMS
The HIPAA page says Sinch has product-level BAAs as an addendum to its terms, but no page we read names the SMS API among them, and the page puts primary HIPAA responsibility on the customer.
Workaround: Ask Sinch whether the SMS API is covered by a BAA before sending health information.
Limited support and audit features for online accounts
No paid support plans are listed for the API, the archived SLA post says online customers have no SLA, and no page we read describes an audit log of console actions.
Workaround: Every account can open a ticket in the support portal, and the Messaging SLA comes with a contract (Order Form).

Pricing reality

Billing is prepaid: you top up a balance in the dashboard and pay per message. A US SMS on a 10DLC or toll-free number is $0.0078, sent or received, plus carrier fees, which the carrier fee article (Oct 1, 2026) lists at $0.0035 for AT&T, $0.0045 for T-Mobile and $0.0050 for Verizon. A 10DLC number is $1.00/mo plus $1.00 setup. 10DLC adds a $4 brand fee, a $15 review fee per campaign submission and a monthly campaign fee billed 3 months up front: $10 for most use cases, or $1.50 for low-volume mixed, which the article limits to under 10k SMS a month. Our scenario sends 10,000, so it takes a $10 campaign: $78.00 + $43.33 carrier fees + $1.00 number + $10.00 campaign + $1.67 one-time fees over 12 months = $134.00 a month (computed). Local taxes are added at top-up, and volume pricing goes through sales.

Exit path

The SMS REST API has list endpoints for batches, delivery reports and inbound messages, and the dashboard has SMS Analytics; no bulk export is named on the pages we read. The Build page describes porting numbers in and moving existing 10DLC (TCR) records over; porting out is not described. The Terms of Service allow termination on 90 days’ written notice, and a prepaid balance earns no interest and may be lost after termination if Sinch cannot refund it.

Compared with

Telnyx Messaging API
Side by side: Sinch SMS API and Telnyx Messaging API
Pick Sinch SMS API when
You want a texting sandbox for tests and a DPA that is part of the online terms.
Pick Telnyx Messaging API when
Price leads: our scenario is $85.89 a month at Telnyx against $134.00 here, with carrier fees and volume tiers on its own pricing page.
Twilio Programmable Messaging
Side by side: Sinch SMS API and Twilio Programmable Messaging
Pick Sinch SMS API when
You want SAML SSO with no plan condition stated, a texting sandbox, and prices for 241 countries in one prepaid account.
Pick Twilio Programmable Messaging when
You need a HIPAA BAA that names SMS, an audit log, carrier fees on the pricing page itself and a slightly lower scenario figure ($130.61 against $134.00).
AWS End User Messaging SMS
Side by side: Sinch SMS API and AWS End User Messaging SMS
Pick Sinch SMS API when
You want a trial credit without a card, a sandbox that does not bill, and carrier fees listed per carrier.
Pick AWS End User Messaging SMS when
You already run on AWS and need a HIPAA BAA for SMS, CloudTrail audit logs and SSO through IAM Identity Center.

Choose it if

You send SMS in many countries and want one prepaid account with a per-country price list.
You want SAML SSO with no plan condition stated, and SMS servers outside the US through your account manager.
You want to test in a sandbox and register 10DLC brands and campaigns by API.

Look elsewhere if

You need carrier and 10DLC fees on the pricing page itself, not in help articles marked "only indications".
You need a HIPAA BAA that names the SMS API.
You want published volume tiers or paid support plans with prices.

Bottom line

From its public pages, Sinch offers a prepaid SMS API with per-country prices, SAML SSO, non-US servers and a SOC 2 Type II for SMS. Its US carrier and 10DLC fees sit in help articles that call them "only indications".

Plan limits at a glance

Limit	As recorded
US SMS rate (10DLC)	$0.0078 per message, outbound or inbound
US carrier fees	Per carrier: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.0050 (outbound; carrier fee article of Oct 1, 2026)
Local number	$1.00/mo plus $1.00 setup
10DLC registration fees	Brand $4, campaign review $15 per submission, $10/mo standard or $1.50/mo low-volume mixed (under 10k SMS/mo); optional vetting $41.50
Reference scenario (10,000 US texts/mo)	$134.00, computed
Free option	Trial credit, no card ($2 for US accounts per archived help); texting sandbox
Volume discounts	Not published; contact sales
SOC 2 / ISO 27001	SOC 2 Type II naming the SMS API; group ISO 27001 certificate
HIPAA BAA	Product-level BAAs offered; SMS API not named
Non-US data region	EU (Ireland, Sweden), Australia, Brazil, Canada through the account manager
Opt-out handling	Automatic STOP blocking once consent management is switched on (Conversation API)
SSO	SAML in Sinch Build; no plan condition stated

Read from the vendor's public pages on Oct 15, 2026. No hands-on run is published yet. How we check

Sinch SMS API lists 6 plans. The cheapest paid plan, Pay as you go, costs $0.0078/message.

Sinch SMS APITrial
Free trial
$0/mo
Trial credit, no card; amount not on the live pages ($2 for US accounts per the archived help article)
- Test number from Sinch; numbers cannot be bought on the trial
- SMS only to your verified numbers (up to 5)
- Texting sandbox and a dry-run endpoint that sends nothing
Sinch SMS API
Pay as you go: US SMS
$0.0078/message
Per outbound or inbound SMS on a 10DLC or toll-free number; carrier fees apply
- Short code SMS $0.009
- MMS $0.02 on 10DLC, $0.018 on toll-free
- Country selector with prices for 241 countries
- Prepaid balance; local taxes added at top-up
Sinch SMS APILowest price
Local number (10DLC)
$1.00/mo
Plus $1.00 one-time setup
- 10DLC fees (fee article, updated Sep 17, 2026): brand $4, campaign review $15 per submission, low-volume mixed campaign $1.50/mo (under 10k SMS a month), most other campaigns $10/mo
- Campaign fees billed 3 months up front
Sinch SMS API
Toll-free number
$2.00/mo
Plus $2.00 one-time setup
- Same $0.0078 per SMS as 10DLC
- Toll-free verification at no cost (help article, updated Aug 11, 2026)
Sinch SMS API
Short code (random)
$500/mo
Lease per the short-code article (updated Sep 29, 2026); the pricing page writes "500 Random or 1000 Vanity MoM" without a currency
- Vanity short code $1,000/mo
- Sinch lease management fee applies; amount not stated
- Carrier setup fees on top
Sinch SMS API
Volume and enterprise
Contact sales
No volume tiers published
- SMPP access, API servers outside the US and callback HMAC or OAuth go through sales or an account manager

Prices as listed, USD, excluding tax; observed 2026-10-15.

Source: sinch.com pricing page. Prices change; the observed date above is when our agent read them.