The Overlooked Power of MMS in SMS and Email Campaigns

In the competitive landscape of digital marketing, SMS and email remain powerful tools—but when used in harmony with MMS, your campaign reach and impact can be significantly elevated. At Cellcast, we help Australian businesses leverage the full potential of multi-channel messaging. A key element often underestimated is how to properly send MMS images, particularly static ones. Done poorly, they fail to reach your customer. Done correctly, they can dramatically increase engagement and conversions.

Here, we break down best practices for optimising static MMS images, ensuring your visual content delivers impact—across both SMS and email journeys.

File Size Matters: Deliverability Starts Here

Carrier networks act as gatekeepers for MMS delivery. If your image file is too large, it may never reach the recipient's device. We recommend:

• Under 500KB when sending without transcoding
• Up to 1MB if your provider supports transcoding (Cellcast’s platform does)
• 300KB or smaller for large-scale sends to prevent message queue delays

Ensuring correct file size helps avoid slow delivery and ensures consistency across campaigns.

Use the Correct Image Dimensions

Portrait orientation is most compatible with modern mobile devices. The optimal ratio is 9:16, or 1080 × 1920 pixels. When viewed inside a messaging bubble, important parts of the image can be cropped. Therefore, keep your content of interest within the visible “safe zones”:

• For 1080 × 1920 px images: avoid placing key content within the top and bottom 250 px
• For 480 × 480 px: avoid the outer 40 px on all sides

This ensures critical messages and visuals remain visible in preview mode.

Choose the Right File Format

• .JPG images load faster and are more widely supported across devices
• .PNG images should avoid transparency, as backgrounds may display unpredictably

Always test your message across Android and iOS devices prior to launch.

Quality vs. Speed: Find the Balance

When sending multimedia via SMS, balance is key. Large, high-quality images can slow delivery or even fail to render correctly on some networks. It’s best to compress your image while maintaining clarity. We advise prioritising legibility and brand consistency over ultra-high resolution.

Combine SMS, Email and MMS for Greater Impact

An optimised MMS image is not a stand-alone feature—it’s part of a smarter multi-channel marketing strategy. Here’s how to build a high-performing flow:

• Email: Provide detailed content or promotional context
• SMS: Deliver urgent nudges or link reminders
• MMS: Showcase product visuals, limited-time offers or invitations using eye-catching imagery

This integration boosts engagement and maximises ROI across all touchpoints.

Final Tips Before Sending

• Validate image size and resolution
• Ensure key visuals are within safe viewing zones
• Preview your MMS on various devices
• Use peak open times to schedule delivery (such as weekday mornings or early evenings)

At Cellcast, we empower Australian businesses to deliver targeted SMS and email campaigns that convert. Our upcoming Email functionality, launching September 2025, will allow you to seamlessly manage SMS, MMS, and email within a single platform—helping you coordinate, automate, and optimise communication across all channels.

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