Yes. Website speed is part of technical SEO, and most SEO companies treat it as a standard area of work. The value they add is less about owning a server and more about diagnosing what is slowing a page down, prioritizing the fixes that matter, and either implementing those fixes or guiding a developer through them. This answer covers what that help actually looks like in practice.
Diagnosis with real tools
The work starts with measurement, not guesswork. An SEO company will run your pages through tools such as Google PageSpeed Insights, the Core Web Vitals report in Google Search Console, and a crawl of the full site. These tools separate two kinds of data: lab tests that simulate a load, and field data that reflects how real visitors experience the page. A good company looks at both, because a page can score well in a lab test and still feel slow for users on mobile connections.
From that data they identify specific problems: oversized images, slow server response time, scripts that block the page from rendering, or layout that jumps around as the page loads. The output should be a concrete list of issues tied to specific pages and templates, not a vague “your site is slow” verdict.
Image and code optimization
Images are usually the largest part of a page’s weight, so they are often the first thing addressed. Typical work includes compressing images, resizing them to the dimensions actually displayed, converting them to modern formats such as WebP or AVIF, and applying lazy loading so off-screen images load only when needed. The hero image is treated as an exception, since lazy loading the main image visitors see first would slow down the page.
On the code side, an SEO company looks at the CSS and JavaScript files a page loads. They reduce unused code, compress files, and address scripts that block rendering by deferring or delaying non-critical JavaScript. Reducing render-blocking resources is often one of the most visible improvements, because it lets content appear sooner.
Caching and server response
Caching stores a ready-made version of a page so the browser or server does not rebuild it from scratch on every visit. An SEO company will review whether browser caching, page caching, and a content delivery network are set up correctly. They also look at initial server response time, since a slow response delays everything that follows. Server and hosting changes usually require coordination with your host or developer, and a competent company will tell you plainly when a problem is rooted in infrastructure rather than the site itself.
Core Web Vitals
Google measures page experience through Core Web Vitals: Largest Contentful Paint, which tracks how quickly the main content loads; Interaction to Next Paint, which measures how responsive the page feels when a user clicks or taps; and Cumulative Layout Shift, which measures unexpected movement of elements as the page loads. Speed work maps directly onto these metrics. Image and server fixes tend to improve loading, trimming JavaScript improves responsiveness, and reserving space for images, ads, and fonts reduces layout shift. An SEO company should report progress against these metrics so you can see whether the work moved the numbers.
Working with developers
Some speed fixes are content-level changes an SEO company can make directly, especially on common platforms. Others, such as theme code, hosting, or how a page is built, sit with a developer. In those cases the SEO company’s role is to write clear, specific tickets, explain why each change matters, and verify the result after it ships. When you ask a company about speed work, it is reasonable to ask which fixes they handle themselves, which require your developer, and how they confirm a change actually improved performance.