If your website has an XML sitemap (and yes—you should), you’re already giving search engines and AI crawlers a clear roadmap to your web pages. Beyond the basics, optional sitemap tags like <lastmod>, <changefreq>, and <priority> add extra metadata and context about your pages. The question for SEO professionals today is: which of these tags still matter for SEO and GEO?
Let’s start with the one that still earns its keep: <lastmod>.
The <lastmod> Tag in an XML Sitemap Tells Crawlers When Content Was Last Updated
The <lastmod> tag communicates the most recent modification date of a webpage, helping both traditional and AI-driven crawlers decide which URLs to revisit. It’s part of the XML schema defined within the <urlset> element, where attributes like xmlns and encoding (often UTF-8) ensure that your sitemap.xml is valid and machine-readable.
By clearly indicating when a page was last modified, <lastmod> supports crawl efficiency. Search engines like Google and Bing use this data to prioritize re-crawling updated pages, reducing wasted crawl cycles on static content.
For large websites—especially ecommerce sites or directories—<lastmod> improves crawl budgeting and ensures fresh content is indexed promptly.
Beyond SEO, this tag plays an emerging role in GEO (Generative Engine Optimization), helping AI-driven ranking systems interpret content freshness and reliability.
In short, <lastmod> remains simple, low-effort, and valuable.
Why Adding <lastmod> to Your XML Sitemap Improves SEO Accuracy and Crawl Efficiency
Adding <lastmod> to your sitemap helps search engines interpret updates accurately and decide when to re-crawl your pages. Bing has publicly confirmed that it uses <lastmod> as a key freshness signal—not only for SEO but also for AI-based algorithms that evaluate content relevance.
Google’s stance is more nuanced. While Google once de-emphasized <lastmod> because of manipulation by black-hat SEOs who faked update dates, the tag still supports technical optimization and helps crawlers allocate resources more efficiently.
When you implement <lastmod>:
- Make sure the timestamp reflects an actual update to your HTML content or metadata.
- Avoid faking updates—false freshness wastes crawl budget and can harm indexing.
- Keep timestamps accurate across your sitemap and canonical URLs.
The bottom line: while <lastmod> alone won’t guarantee higher Google rankings, it improves crawl intelligence and provides valid freshness cues for both SEO and GEO.
How the <lastmod> Tag Strengthens GEO and AI Search Visibility
For GEO—Generative Engine Optimization—<lastmod> acts as a freshness and credibility signal for AI systems and large language models (LLMs). These systems rely on accurate update metadata to determine which web pages are current, useful, and reliable.
In practice, <lastmod> supports GEO in several key ways:
- It helps AI algorithms and generative engines prioritize pages that are recently updated.
- It enhances the accuracy of AI search summaries, where recency often boosts content trust.
- It complements other crawl directives like robots.txt, noindex, and canonical tags by adding clarity around update timing.
This tag is especially valuable for dynamic sites—like ecommerce platforms or WordPress-based businesses—where content and product listings frequently change.
However, <lastmod> is only effective if the updates are genuine. AI engines are increasingly capable of detecting unchanged HTML structures or content that hasn’t truly been refreshed.
So yes, include <lastmod>—but back it up with authentic, meaningful updates to your content and metadata.
Why You Should Skip <changefreq> and <priority> in Your Sitemap
Modern crawlers no longer rely on <changefreq> or <priority> tags, so including them adds no real value. Both Google and Bing have confirmed that they ignore these tags when deciding crawl frequency or importance.
Historically, these elements were designed to hint at how often a page changes or how critical it is compared to others. However, today’s AI and GEO algorithms rely on real data—engagement metrics, user behavior, and link structure—rather than static hints.
Here’s what to know:
- <changefreq> and <priority> don’t influence rankings or crawl schedules anymore.
- Yahoo and other legacy search engines have also deprecated these signals.
- Modern sitemap formats for videos and images use real interaction data, not priority values.
You may have heard of llms.txt, a proposed file format for optimizing AI crawler behavior. For now, there’s no verified benefit or support across major AI search systems. Instead, focus on essentials like valid XML structure, accurate URLs, and clean sitemap indexing.
In short: keep your sitemap lean—use only <loc>, <urlset>, <lastmod>, and proper encoding.
How <lastmod> and a Clean Sitemap Improve Crawl Efficiency, Cost, and Sustainability
Using <lastmod> correctly and cleaning up your sitemap.xml isn’t just about better crawl management—it’s also about efficiency, cost savings, and environmental responsibility.
Every unnecessary crawl or redundant data fetch increases file size, wastes bandwidth, and consumes extra energy. At internet scale, those inefficiencies translate into higher costs and carbon impact.
By maintaining an accurate sitemap with valid <lastmod> tags:
- You reduce redundant crawling by AI and search bots.
- You improve server performance and response times.
- You make indexing more accurate for both local and global search results.
A well-structured sitemap (encoded in UTF-8 and properly validated) also supports faster AI data ingestion, making GEO systems more efficient overall.
If you’re managing your own site, consider using a WordPress sitemap generator plugin to automate creation and validation. Always check your XML in Google Search Console or Bing Webmaster Tools to ensure full compliance.
This is not only good SEO practice—it’s good digital citizenship.
Bottom Line
Keep <lastmod> in your sitemap.xml.
Skip <changefreq> and <priority>.
Use accurate timestamps, validate your xml file, and maintain a clean structure.
And think about the bigger “why”—building a web ecosystem that’s smarter, cleaner, and more efficient.
For expert help in technical SEO, sitemap cleanup, and AI-driven search optimization, explore our SEO services or learn more about how we structure sitemaps and GEO strategies at V9 Digital
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Common Questions About XML Sitemaps, <lastmod>, and GEO
1. What is the purpose of an XML sitemap for SEO and GEO?
An XML sitemap provides search engines and AI crawlers with a structured map of your website, improving indexation and visibility. A valid sitemap.xml includes properly encoded <urlset>, <loc>, and <lastmod> tags that help crawlers navigate your content efficiently.
2. Should I include <changefreq> and <priority> tags in my sitemap?
No. Google, Bing, and Yahoo ignore these tags. They no longer influence crawl behavior or rankings and add unnecessary clutter to your XML file.
3. How does <lastmod> affect SEO performance?
The <lastmod> tag helps crawlers detect recent updates, making re-crawling more efficient. While it doesn’t directly improve rankings, it supports better crawl management for frequently updated websites like ecommerce platforms or local directories.
4. Can <lastmod> improve local SEO and geolocation accuracy?
Yes. Freshness signals from <lastmod> can enhance local search visibility, especially when combined with structured data such as geotags and updated meta information. This helps AI systems and Google Maps display more relevant, current results.
5. What’s the difference between XML and HTML sitemaps?
XML sitemaps are machine-readable files designed for crawlers and contain elements like <urlset>, xmlns, and <loc>. HTML sitemaps are user-facing pages that help visitors manually navigate your site. Both have unique roles in SEO and GEO strategies.
6. How often should I update my sitemap.xml?
Update your sitemap whenever content is added, removed, or significantly modified. Each <lastmod> tag should correspond to a genuine update in your content, metadata, or internal linking.
7. Can optimizing my sitemap reduce crawl cost and improve efficiency?
Yes. Clean, accurate sitemap files minimize redundant crawling and reduce server strain, resulting in faster indexing and lower environmental impact. It’s a simple optimization with measurable benefits.
8. What tools help validate a sitemap.xml file?
You can validate using Google Search Console, Bing Webmaster Tools, or third-party XML validators that check schema, syntax, and encoding. Always ensure UTF-8 encoding and valid response codes for every listed URL.