SMS gets more clicks and faster attention per message than email, while email costs far less per send and carries more content, so neither channel “beats” the other everywhere. Use SMS for short, time-sensitive messages to people who opted in to texts, use email for richer content and lower-urgency updates, and judge both on revenue per message rather than open rates; the SMS campaign features you choose decide how well you can measure that.
This guide compares the two on engagement, cost, measurement and rules, using published 2025 and 2026 benchmarks, and shows how to work out ROI for SMS, email, social and other channels with your own numbers.
How do SMS and email marketing compare at a glance?
| Factor | SMS | |
|---|---|---|
| Message length | 160 GSM-7 characters per part (70 in Unicode) | Practically unlimited, with images and layout |
| Average campaign click rate | 5.6% (Klaviyo, 2026) | 1.69% (Klaviyo, 2026) |
| Average campaign order rate | 0.27% (Klaviyo, 2026) | 0.16% (Klaviyo, 2026) |
| Automated flow order rate | 1.9% (Klaviyo, 2026) | 2.11% (Klaviyo, 2026) |
| Cost per message | Cents per message part, varies by country | Fractions of a cent on most plans |
| Open tracking | Not available; delivery reports and link clicks instead | Available but inflated by privacy features |
| Best for | Urgent, short, action-led messages | Content, newsletters, detailed offers |
Sources: Klaviyo’s 2026 SMS benchmarks (over 183,000 customers, published January 2026) and 2026 email benchmarks (over 205,000 brands).
Is the SMS open rate really 98%?
You will see “98% of texts are opened” quoted everywhere, usually without a traceable study. The honest answer is that nobody can measure an SMS open rate. SMS has no read receipt. A delivery report tells you the handset received the message, not that anyone read it.
Email open rates have their own problem. Mailchimp’s benchmarks put the all-industry average at 35.63% (data last updated December 2023) but warn that Apple’s Mail Privacy Protection affects open-rate accuracy, because opens can be recorded automatically. Klaviyo’s 2026 figure is 31% for campaigns.
So compare channels on what both can measure: delivery, clicks, orders and revenue. For SMS, that means tracked short links and delivery reports on every campaign.
Which channel gets more clicks and orders?
On campaigns, SMS wins on engagement in every major dataset we found:
- Klaviyo reports a 5.6% average click rate for SMS campaigns against 1.69% for email campaigns, and a 0.27% order rate against 0.16%.
- Omnisend’s 2026 SMS benchmarks, based on 246 million SMS campaign sends across 27,000+ brands in 2025, show a 12.39% SMS campaign click-through rate against 0.74% for email campaigns.
Automations tell a more balanced story. In Klaviyo’s data, email flows convert slightly better than SMS flows (2.11% against 1.9% placed order rate). Omnisend found automated emails earned $3.41 per message against $0.75 for automated SMS. Email’s longer format sells well once someone is already engaged, especially in welcome and post-purchase flows.
Note the numbers differ between platforms because each defines click rate differently. Compare within one dataset, never across them.
What does each channel cost per message?
Email is far cheaper per send. As an example, Omnisend’s published Standard plan costs $11.20 a month for 6,000 emails (September 2026), under $0.002 per email.
SMS is priced per message part and per destination country. SMS.to’s published price starts from $0.023 per SMS and varies by country; see the SMS price list by country. Three things change the real cost:
- Encoding. One GSM-7 part holds 160 characters. Add an emoji and the message switches to Unicode, 70 characters per part, which can double or triple the cost.
- Destination. Termination rates differ widely between countries and networks.
- List quality. SMS is normally billed when it is sent, even if it never arrives, so removing dead numbers saves money.
Our guide to SMS pricing and character limits works through the maths.
How does SMS ROI compare with email, social and other channels?
There is no universal ROI figure worth quoting, because ROI depends on your margin, list, market and attribution model. Calculate it per channel with the same formula:
ROI = (attributed revenue minus channel cost) divided by channel cost
A worked example with illustrative numbers, not benchmarks: a store sends one SMS campaign to 10,000 subscribers at $0.03 per message, a total of $300. If tracked links attribute 30 orders at an average of $60, revenue is $1,800 and ROI is (1,800 minus 300) divided by 300, or 5 to 1. The same offer by email to 40,000 subscribers might cost $80 and bring 60 orders; its ROI would be far higher, even though each email converts less often.
That is why the two work together. Email usually wins on ROI for broad content because it is cheap to send. SMS wins where speed changes the result: abandoned baskets, flash sales, restocks, delivery updates and appointment reminders.
For other channels, apply the same discipline:
- Organic social costs little per post, but reach depends on each platform’s algorithm, so you cannot guarantee who sees a message.
- Paid social and search are best for acquiring new customers; you pay per impression or click, so compare cost per order, not cost per message.
- Push notifications are nearly free but only reach people who installed your app and allowed notifications.
- SMS and email reach people who gave you their details, which makes them retention channels you own.
Measure all of them with holdout tests where you can: keep a small share of your audience out of a campaign and compare their purchases with everyone else’s. That shows incremental revenue, not just attributed revenue.
Do the same rules apply to SMS and email?
Often, yes, but the details differ by country:
- UK: the ICO’s PECR guidance applies one electronic marketing rule to emails and texts alike, including the soft opt-in for existing customers who were offered an opt-out when you collected their details and in every message.
- US email: the FTC’s CAN-SPAM compliance guide requires you to honour opt-outs within 10 business days.
- US SMS: the FCC’s TCPA rules in 47 CFR 64.1200 require prior express written consent for automated telemarketing to mobile numbers, which covers most marketing texts, and sending from local numbers needs 10DLC registration. Our 10DLC vs short code vs toll-free guide explains the sender options.
Whatever the market, keep consent records and include an easy opt-out in every marketing message. See our SMS marketing compliance guide for automated opt-outs.
When should you use SMS, email or both?
| Use case | Best channel | Why |
|---|---|---|
| Flash sale ending today | SMS | Urgency; a text is noticed quickly |
| Monthly newsletter | Long content, images, low cost | |
| Abandoned basket | Both | Email first with product images, SMS reminder hours later |
| Delivery delay | SMS | Time-sensitive service update |
| Order receipt and invoice | Customers keep and search it | |
| Back-in-stock alert | SMS | First buyers win limited stock |
| Appointment reminder | SMS | Short, timely, cuts no-shows |
| Product education or guides | Needs space and visuals |
A practical rule: send by email when the message can wait a day, by SMS when it cannot, and never send the same promotion on both at the same moment. For ecommerce flows that combine the two, see SMS marketing for ecommerce, and for more data, our SMS marketing statistics round-up.
How SMS.to helps you measure SMS against email
Fair comparisons need clean measurement. The SMS.to features built for this include tracked short links that record clicks per campaign and support A/B tests, delivery reports for every message, personalisation with dynamic tags, and a one-click opt-out link. You can send campaigns from the web platform or trigger them from your own systems over the API, and pay per message with no contracts.
FAQs
Is SMS marketing more effective than email?
For short, urgent campaigns, SMS usually gets more clicks and orders per message. For content and low-cost reach, email often delivers better ROI. Most brands get the best results using both.
What is a good SMS click rate?
Klaviyo’s 2026 benchmarks put the average SMS campaign click rate at 5.6%, with the top 10% above 10%. Benchmarks vary by platform and industry.
Why is SMS more expensive than email?
Each SMS is carried and billed by mobile networks, and the rate depends on the destination country. Email delivery costs almost nothing per message once you pay for the platform.
Should I send the same campaign by SMS and email?
Not at the same time. Lead with email for detail and follow up by SMS only for people who have not acted, or use SMS where timing matters.
Ready to run your own SMS against email test? Create a free account, no credit card needed, and send a tracked campaign to a small segment first.
