How Does an SEO Company Improve a Website’s On-Page SEO?

An SEO company improves on-page SEO one URL at a time. It crawls the site, then rewrites missing, duplicated or off-target titles and meta descriptions, fixes the heading hierarchy, adds and validates structured data, renames images and writes alt text, cleans URLs and sets canonical tags on duplicates. The result is a sheet with one row per URL, checked afterward against the live results and Search Console.

Which Pages Get Worked On First

Start where the data shows a gap. In Search Console’s Performance report, pages with many impressions and a low click-through rate for their position are the first candidates for title and description work, followed by the pages that bring leads or sales and any page the crawl flags with a missing or duplicate title. A missing title or a duplicate description can be fixed at once. Heavier re-optimization should wait until a page’s content and target query are right; the strategies an SEO company uses to improve rankings shows where on-page work sits among the other categories.

Title Tags: What Google Uses and When It Rewrites

The audit begins with a crawl in Screaming Frog or Sitebulb that lists every title that is missing, duplicated, over 60 characters or under 30. Then comes the part a client may not expect: Google does not always show the title tag. Its documentation on how title links are created says the process “is completely automated” and draws on several sources, including the title element, the main visual title on the page, heading elements such as the H1, og:title tags and the text of links pointing to the page.

Two studies show how often the title tag is replaced, using different samples and definitions:

Ahrefs’ study of 953,276 pages ranking in the top 10 (November 16, 2021) found Google used the title tag 66.6% of the time, counting minor differences as a match, and 7.4% of those pages had no title tag at all. When Google did not use the title tag, it took the H1 50.76% of the time.
Zyppy’s study of 80,959 titles across 2,370 sites, collected in early 2022 and compared with desktop results, found 61.6% were rewritten. Titles of 51 to 60 characters had the lowest rewrite rates (39% to 42%), titles over 70 characters were rewritten 99.9% of the time, and pipes used as separators were removed or replaced 41.0% of the time, while dashes were removed 19.7% of the time.

Because the two studies count differently, compare neither figure with the other; together they show that rewriting happens at scale. Both point the same way on the H1: Zyppy found that matching the H1 to the title reduced rewriting, and Ahrefs found the H1 was Google’s most used substitute.

The working rule that follows: state the page’s topic early, keep the title around 51 to 60 characters, and make the H1 say the same thing. For example, imagine a plumbing company whose service page is titled “Services”. A rewrite would read “Emergency Plumbing Repair in Dallas, TX: Same-Day Service” (57 characters), with an H1 that matches. Google notes that it has to recrawl a page to notice changes, which “may take a few days to a few weeks”. After that window, search for the target queries and check whether Google shows the new title; Search Console’s Performance report then shows whether clicks and click-through rate changed.

Meta Descriptions: A Suggestion Google May Replace

Google’s guidance on meta descriptions says snippets “are primarily created from the page content itself” and that Google sometimes uses the meta description “if it might give users a more accurate description of the page than content taken directly from the page.” Ahrefs’ meta description study (October 9, 2020), comparing descriptions with desktop snippets for 20,000 keywords, found Google rewrote them 62.78% of the time: 59.65% for high-volume head terms and 65.62% for long-tail terms. It also found 25.02% of top-ranking pages had no meta description.

A description still does a job when Google shows it: it is the pitch under the title. Google’s guidance sets no length limit and says the snippet is truncated “as needed,” so put the main point first. It also asks for unique descriptions, since identical ones across a site “aren’t helpful” when individual pages appear in results. A single template description copied onto every page is the first thing to fix.

Headings: One Clear Hierarchy

Heading work is about structure:

One H1 that states the page’s topic and agrees with the title. That is our convention, and the reason is the title-link behavior above: Google may use the H1 in the result.
H2s for the main sections, in a logical order.
H3s nested under H2s, without skipping a level.
No heading tags used only for visual styling.

If your theme marks a sidebar widget, footer label or “Related Posts” block as an H2 or H3, those labels sit in the page’s outline next to its section headings. Ask the agency to check the rendered heading list, not only the editor view. Writing headings that match search intent belongs to content work, laid out in how an SEO company optimizes content for search engines.

Structured Data: What It Can and Cannot Earn

Structured data, written in JSON-LD with the Schema.org vocabulary, labels what a page contains. Schema.org types such as LocalBusiness (name, address, phone, hours), Article and Product describe a business, a post or an item for sale. The agency adds the markup through a plugin such as Rank Math or Yoast on WordPress, or by hand on a custom site, and validates it with Google’s Rich Results Test before launch.

Three limits belong in the proposal:

Valid markup makes a page eligible; it does not guarantee a result. Google’s structured data guidelines state: “Google does not guarantee that your structured data will show up in search results, even if your page is marked up correctly according to the Rich Results Test.”
FAQ rich results are gone. Google’s Search Central changelog says of the FAQ rich result: “This feature will no longer appear in Google Search starting May 7, 2026.” Google removed its how-to structured data documentation in September 2023 because that rich result was no longer shown.
Sitelinks are not a markup feature. Google’s sitelinks documentation says “At the moment, sitelinks are automated.” What helps is informative titles and headings, a logical site structure and concise internal anchor text.

Images: File Names and Alt Text

Alt text serves two readers: screen readers for people who cannot see the image, and search engines. Google’s image SEO guidance says it uses alt text along with computer vision algorithms and the contents of the page to understand what an image shows, so alt text adds context rather than standing in for the image. The fix is mechanical. Rename camera files such as IMG_4821.jpg to descriptive, hyphenated names (for example, dallas-emergency-plumber-water-heater-repair.jpg), update every page that references the old file name, and write alt text that describes the image in a short sentence. For example, “Plumber repairing a tankless water heater in a Dallas home” serves both readers; “plumber Dallas plumber emergency plumber Dallas TX” serves neither and reads as spam.

URLs and Canonical Tags

At the page level, URLs are cleaned for readability: lowercase, hyphens rather than underscores, no session IDs or unneeded parameters. How URLs map to the site’s hierarchy belongs with the structure work in how an SEO company optimizes website structure.

Duplicate versions of a page (parameter URLs, printer versions, near-identical variants) get a canonical tag pointing to the preferred URL. The agency should then confirm in Search Console’s URL Inspection tool that Google selected that canonical, because Google treats the tag as a signal, not a command. How an SEO company improves crawlability and indexing covers the canonical and indexing mechanics.

What a Finished On-Page Pass Should Show You

Ask to see the per-URL sheet before work starts: one row per URL with the current and proposed title, meta description and H1, the schema type and the canonical status. After launch, the first check, once the recrawl window has passed, is a search for the target queries to see whether Google shows the new titles. The second is a Search Console click-through comparison for the same pages at a similar average position, read 60 to 90 days after the change (our recommended window, long enough to smooth week-to-week noise). Without both the sheet and that comparison, you cannot tell what the pass changed.