On this page · 12 sections
- What US and UK teams need to do before 2027 traffic starts
- Twilio: highest base rate, broadest add-ons
- Plivo: lower base rate, cheapest number rental
- Telnyx: lowest US platform fee, published carrier passthrough
- US cost per message, side by side
- US registration and verification fees
- UK rates and sender ID rules
- Decision table: choose X if
- Worked monthly cost: a SaaS company sending 120,000 texts
- Implementation checklist
- How eCorpIT can help
- References
Summary. In the US, Twilio, Plivo and Telnyx differ on the platform fee; the carrier surcharges on top are almost the same. On 13 November 2026, Twilio lists outbound US SMS at $0.0083 per segment, Plivo at $0.0077 on long codes and short codes ($0.0079 on toll-free), and Telnyx at $0.004 per part on local numbers. All three pass through $0.0035 for AT&T and $0.0045 for T-Mobile; for Verizon, Twilio and Plivo list $0.005 and Telnyx $0.0045. Registration fees are set by The Campaign Registry (TCR) and passed through: $4.50 per brand, $15 per campaign vetting and $10 a month for a standard campaign, while Twilio's Standard brand costs $46 because it includes vetting. Unverified toll-free numbers have been blocked since 31 January 2024. In the UK, Twilio charges $0.056 per outbound SMS and Plivo $0.0486 to $0.0556 on the four main networks; we could not read Telnyx's UK rates. For 100,000 US texts a month we estimate $1,272 on Twilio, $1,211 on Plivo and $827 on Telnyx. Pick Telnyx for the lowest US unit cost, Plivo for cheap numbers and per-network UK rates, and Twilio for its compliance and fraud add-ons.
About this article. For product and engineering leads choosing an SMS provider for US and UK passcodes and alerts. We checked every rate, fee and rule against each vendor's own pricing pages, documentation and support articles, and against guidance from the Information Commissioner's Office (ICO), on 13 November 2026. Prices are pay-as-you-go list prices in US dollars, before tax and any negotiated discount; vendors change them often, so re-check before you commit. This is not legal advice, and no vendor paid for inclusion. Researched with AI assistance and reviewed by our editorial team.
What US and UK teams need to do before 2027 traffic starts
Three rules decide whether messages arrive at all.
Register 10DLC numbers before you send. Plivo's documentation says messages from US long codes that are not linked to a registered campaign will not be delivered; Twilio and Telnyx run the same TCR process. The current TCR fee schedule took effect on 1 August 2025: brand registration rose from $4.00 to $4.50, standard vetting from $40.00 to $41.50 and vetting appeals from $10.00 to $11.00, and a new Authentication Plus fee of $12.50 applies to public, for-profit brands. Twilio charges it on each retry. Plivo lists it as a one-time fee. Start registration weeks before launch.
Verify toll-free numbers. Twilio says that since 31 January 2024, messages from toll-free numbers that are unverified or pending verification are blocked across the US and Canada. It asks you to allow about three to five business days for its own processing, and verified numbers get three SMS segments per second by default. Telnyx's documentation adds that new toll-free submissions have needed three business registration number fields since 17 February 2026.
In the UK, avoid generic sender IDs. Twilio's UK guidelines say operators block generic alphanumeric sender IDs, and from 1 November 2023 the blocked list grew to include names such as OTP, 2FA, Code, Login, Bank and Delivery. Use your brand name, and pre-register it with Twilio if it is on the MEF or BT protected lists.
Two easy-to-miss costs: Twilio charges a $0.001 processing fee on every message that ends in a failed status, in the US and the UK. And Telnyx adds $0.10 a month to each number to enable SMS and MMS, on top of the rental.
Twilio: highest base rate, broadest add-ons
US rates. $0.0083 per outbound or inbound SMS segment on long codes, toll-free numbers and short codes, and $0.05 on free-to-end-user (FTEU) short codes. Outbound MMS is $0.022. Carrier fees on long codes: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.005, US Cellular $0.005 and all other carriers $0.0042. Volume discounts were not shown, so we used list rates.
US numbers. A long code costs $1.15 a month and a toll-free number $2.15. Random short codes are $1,000 a month and vanity short codes $1,500, both billed quarterly with a one-time setup fee.
10DLC registration (passed through). Sole Proprietor and Low Volume Standard brands cost $4.50 one time; a Standard brand costs $46 and includes secondary vetting. Each campaign has a $15 vetting fee, then a monthly fee: $10 for standard use cases, $1.50 for low-volume mixed, $2 for sole proprietor, $3 for charity and $5 for emergency services. Twilio points senders under 6,000 messages a day to the Low Volume Standard brand. Twilio's 10DLC product page still shows older $44 and $4 brand fees; its brand documentation confirms $4.50 plus $41.50 vetting.
UK rates. $0.056 per outbound SMS from a UK mobile number or an alphanumeric sender ID, $0.0524 from a short code, and $0.0075 inbound. Alphanumeric sender IDs are free to use. Clean mobile numbers cost $2.50 a month, local numbers $1.15 and a high-volume short code $1,667.
Add-ons. The Engagement Suite (link shortening, click tracking and scheduling) is $0.015 per outbound SMS after 1,000 free a month, and the Compliance Toolkit is $0.015 per US message. SMS pumping protection on UK traffic is $0.025 per message.
Best for: teams already on Twilio, products that need short codes or RCS alongside SMS, and buyers who want vendor-run compliance and fraud tooling.
Plivo: lower base rate, cheapest number rental
US rates. $0.0077 per SMS on long codes and short codes and $0.0079 on toll-free, inbound or outbound. MMS is $0.018 on long codes. Carrier surcharges match Twilio's on the main networks: AT&T $0.0035, T-Mobile $0.0045 outbound and $0.0025 inbound, Verizon $0.005, and US Cellular and other networks $0.005 on long codes.
US numbers. Long codes are $0.50 a month and toll-free numbers $1.00. Short codes are $500 a month (regular) or $1,000 (vanity), billed quarterly, plus a $1,500 one-time fee.
10DLC registration. Plivo's table matches the 1 August 2025 TCR schedule: brand $4.50, optional brand vetting $41.50, appeal $11, campaign vetting $15, and $10 a month per campaign ($1.50 for low volume), billed quarterly. Plivo recommends paid vetting above 6,000 messages a day.
UK rates. Plivo prices UK traffic by destination network. On the four main networks: EE $0.0486, Vodafone $0.0509, O2 (Telefonica UK) $0.0516 and Three (Hutchison 3G) $0.0556. Across all listed mobile routes the range is $0.0449 to $0.0602; the headline starting price of $0.0372 is the landline route. Inbound is $0.0030. Local numbers cost $0.85 a month and mobile numbers $0.90.
A note on Plivo's calculator. Plivo's pricing pages include a calculator that puts Twilio 50% higher in the US and 59% higher in the UK at 100,000 messages a month. Plivo says it uses effective rates for typical volumes, not list rates, and a Twilio rate from May 2026, so use the rate tables.
Best for: cost-conscious US senders who rent many numbers, and UK senders who want to see the price by network.
Telnyx: lowest US platform fee, published carrier passthrough
US rates. $0.004 per message part on local numbers (which include 10DLC), inbound or outbound, with no platform fee. Toll-free is $0.0055 and short code $0.007. MMS is $0.015 on local numbers. Automatic volume discounts start above 100 million local messages a month. Telnyx's own worked example of 1 million parts shows $4,000 in Telnyx fees plus $3,800 in blended US carrier passthrough, $7,800 in all.
Carrier passthrough. On local numbers: AT&T $0.0035, T-Mobile $0.0045, Verizon $0.0045 and US Cellular $0.005, with smaller carriers listed individually. Telnyx's 10DLC fees article still shows older carrier figures (for example $0.003 for AT&T); we used the pricing page.
Numbers. Local and toll-free numbers start at $1 a month, plus $0.10 a month to add SMS and MMS. Discounts apply above 50 numbers a month.
10DLC registration. Telnyx lists a $4.50 brand application fee, $15 per campaign review, and monthly campaign fees of $10 for standard use cases, $1.50 for low-volume mixed, $2 for sole proprietor, $3 for charity, $5 for emergency and $30 for agents and franchises. It bills the first three months of campaign fees up front and says it adds no markup. A campaign may go to carriers for review more than once, and each review costs $15 unless you tell Telnyx in advance.
UK rates. Telnyx's country pricing pages now redirect to the US rate card, so we could not read its UK rates and have left Telnyx out of the UK figures. Its UK guidelines say alphanumeric sender IDs work without registration, except names protected on the MEF registry. Ask Telnyx for a UK quote.
Commitments. Pay as you go has no minimum. The Growth plan needs $2,000 a month in spend and gives 15% off voice, messaging and numbers. Enterprise starts at $5,000 a month.
Best for: high-volume US senders, teams comfortable with a self-serve API, and anyone whose margin depends on cost per OTP.
US cost per message, side by side
Sources: each vendor's US rate card and number pricing on 13 November 2026.
| US outbound SMS (13 Nov 2026) | Twilio | Plivo | Telnyx |
|---|---|---|---|
| 10DLC long code base rate | $0.0083 | $0.0077 | $0.004 |
| Toll-free base rate | $0.0083 | $0.0079 | $0.0055 |
| Short code base rate | $0.0083 | $0.0077 | $0.007 |
| AT&T carrier fee (long code) | $0.0035 | $0.0035 | $0.0035 |
| T-Mobile carrier fee (long code) | $0.0045 | $0.0045 | $0.0045 |
| Verizon carrier fee (long code) | $0.005 | $0.005 | $0.0045 |
| All-in, long code, to AT&T | $0.0118 | $0.0112 | $0.0075 |
| All-in, long code, to Verizon | $0.0133 | $0.0127 | $0.0085 |
| Long code rental per month | $1.15 | $0.50 | From $1.10 with SMS |
| Toll-free rental per month | $2.15 | $1.00 | From $1.10 with SMS |
| Failed-message fee | $0.001 | Not listed | Not listed |
Every price is per 160-character GSM-7 segment. Twilio's UK guidelines give a 70-character limit for Unicode, so one emoji or unsupported character can push a short message into two or more segments, and the bill with it.
US registration and verification fees
Sources: each vendor's fee pages and documentation.
| Fee | Twilio | Plivo | Telnyx |
|---|---|---|---|
| Brand registration | $4.50 (Sole Prop, Low Volume Standard); $46 Standard incl. vetting | $4.50 | $4.50 |
| Optional brand vetting | Included in $46 Standard | $41.50 | Not on the fees page we checked |
| Campaign vetting | $15 | $15 | $15 per carrier review |
| Standard campaign, monthly | $10 | $10, billed quarterly | $10, first 3 months up front |
| Low-volume mixed campaign, monthly | $1.50 | $1.50 | $1.50 |
| Authentication Plus | $12.50 per retry | $12.50 one time | Not on the fees page we checked |
| Toll-free verification fee | None listed | None listed | None; per-message cost only |
UK rates and sender ID rules
Twilio and Plivo publish UK rates in US dollars.
| UK SMS (13 Nov 2026, USD) | Twilio | Plivo |
|---|---|---|
| Outbound from a UK number | $0.056 | $0.0486 to $0.0556 on the four main networks |
| Outbound from an alphanumeric sender ID | $0.056 | Not listed on the UK page |
| Inbound | $0.0075 | $0.0030 |
| Mobile number rental | $2.50 a month | $0.90 a month |
Sender ID rules from Twilio's UK guidelines. Alphanumeric sender IDs need no operator pre-registration in the UK, apart from protected names, and they are one-way: customers cannot reply. Operators have begun rejecting sender IDs with special characters; Twilio recommends letters, digits, spaces, periods, dashes, underscores and ampersands only. International long codes are not supported for UK delivery. UK short codes take 8 to 12 weeks to provision and need express consent from each recipient.
UK marketing rules. The ICO's guidance on the Privacy and Electronic Communications Regulations (PECR) treats texts as electronic mail: you must not send marketing texts to individuals without specific consent, apart from the soft opt-in for your own previous customers, who must be offered an opt-out in every message. Purely administrative messages, which the ICO calls service messages, are not direct marketing; in our reading that covers one-time passcodes, but adding a promotional line to one makes it marketing. The ICO notes its PECR guidance is under review following the Data (Use and Access) Act.
Decision table: choose X if
| Choose | If |
|---|---|
| Telnyx | US volume is high, cost per message drives the decision, and you are comfortable with self-serve onboarding. |
| Plivo | You rent many US numbers ($0.50 each) or want UK prices by network. |
| Twilio | You need short codes, RCS, a compliance toolkit or SMS pumping protection from one vendor, or you already run production traffic there. |
| Two providers | OTP delivery is critical to revenue. Run a primary and a fallback route, and register brands and campaigns with both. |
| An alternative to SMS OTP | Most users are on apps where passkeys or carrier network APIs can replace the text. |
For the last row, see our passkeys vs SMS OTP comparison and our MWC 2027 briefing on network APIs.
Worked monthly cost: a SaaS company sending 120,000 texts
Assumptions (ours, not vendor figures). A US and UK SaaS company sends 100,000 single-segment OTP and account-alert texts a month in the US and 20,000 in the UK. US traffic runs on two 10DLC long codes under one Standard brand and one standard campaign, with an assumed carrier mix of AT&T 35%, T-Mobile 35% and Verizon 30%. UK traffic uses an alphanumeric sender ID on Twilio and a UK mobile number on Plivo, with an assumed network mix of EE 35%, O2 25%, Vodafone 25% and Three 15%. Telnyx is costed for the US only. Pay-as-you-go list prices, no inbound traffic, no failed messages, taxes excluded.
US blended carrier fee.
- Twilio and Plivo: 0.35 × $0.0035 + 0.35 × $0.0045 + 0.30 × $0.005 = $0.0043 per message.
- Telnyx: 0.35 × $0.0035 + 0.35 × $0.0045 + 0.30 × $0.0045 = $0.00415 per message.
US monthly.
- Twilio: ($0.0083 + $0.0043) × 100,000 = $1,260; two numbers $2.30; campaign $10. Total $1,272.30.
- Plivo: ($0.0077 + $0.0043) × 100,000 = $1,200; two numbers $1.00; campaign $10. Total $1,211.00.
- Telnyx: ($0.004 + $0.00415) × 100,000 = $815; two SMS-enabled numbers 2 × $1.10 = $2.20; campaign $10. Total $827.20.
UK monthly.
- Twilio: 20,000 × $0.056 = $1,120 (alphanumeric sender ID, no rental).
- Plivo: 0.35 × $0.0486 + 0.25 × $0.0516 + 0.25 × $0.0509 + 0.15 × $0.0556 = $0.050975 per message; × 20,000 = $1,019.50, plus a $0.90 mobile number. Total $1,020.40.
| Monthly cost (USD) | Twilio | Plivo | Telnyx |
|---|---|---|---|
| US messages and carrier fees | $1,260.00 | $1,200.00 | $815.00 |
| US numbers and campaign fee | $12.30 | $11.00 | $12.20 |
| US total | $1,272.30 | $1,211.00 | $827.20 |
| UK messages and numbers | $1,120.00 | $1,020.40 | Quote needed |
| Total per month, US and UK | $2,392.30 | $2,231.40 | US only: $827.20 |
| Total per year | $28,707.60 | $26,776.80 | US only: $9,926.40 |
| One-time US registration | $61 ($46 brand + $15 vetting) | $19.50 ($61 with optional vetting) | $19.50, plus 3 months of campaign fees up front |
What moves the answer.
- Carrier fees are the floor. About $415 to $430 per 100,000 US messages goes to carriers on any vendor, so the US gap between Twilio and Telnyx (about $445 a month) is almost all platform fee.
- Low-volume registration. At roughly 3,300 messages a day, this company sits under Twilio's 6,000-a-day line for a Low Volume Standard brand ($4.50 instead of $46) and could consider a low-volume mixed campaign at $1.50 a month. That campaign type is limited to 2,000 segments a day to T-Mobile, so check your T-Mobile share first.
- Unicode. If 10% of messages contain an emoji and split into two segments, US message costs rise by about 10% on every vendor.
- Failed messages. On Twilio, a 2% failure rate adds 2,000 × $0.001 = $2 a month: small, but a useful deliverability signal.
- Commitments. Telnyx's Growth plan (15% off with a $2,000 monthly minimum) and Twilio's committed-use discounts only pay off well above this volume.
If OTP sits inside a hosted login, add the identity provider's per-user charges; our Auth0 vs Clerk vs Amazon Cognito comparison covers those.
Implementation checklist
- Register your US brand and first campaign before writing production code, choosing Low Volume Standard under 6,000 messages a day; each campaign review costs $15.
- Submit toll-free verification as soon as you buy a toll-free number.
- Keep OTP templates in GSM-7 characters and under 160 characters to stay at one segment. If your Android app reads codes automatically, our Android 17 SMS OTP guide covers the message format.
- In the UK, choose a branded alphanumeric sender ID, avoid generic names, and use a mobile number only where customers must reply.
- Keep marketing and transactional messages separate in templates and consent records, so PECR and campaign use-case declarations stay accurate.
- Turn on geographic permissions and rate limits for OTP routes to limit SMS pumping.
- Log carrier, segment count and delivery status per message, and reconcile each invoice.
- Put the provider behind your own messaging service so you can add a fallback route or switch vendors without touching product code.
How eCorpIT can help
eCorpIT is a Gurugram-based technology organisation, founded in 2021, assessed at CMMI Level 5 and MSME certified, with senior-led engineering teams working across AWS, Microsoft and Google platforms. Our application development services team builds OTP, notification and two-way messaging features, including a provider layer that lets you run Twilio, Plivo or Telnyx side by side. Talk to us at /contact-us/.
Last updated: 13 November 2026.
