Yes, to a real extent, especially early on, writing helpful content, basic on-page optimization like clear titles and headings, setting up a Google Business Profile, and monitoring free tools like Search Console are all learnable without deep technical expertise, and business owners often understand their own customers better than an outside writer would.
Where DIY SEO tends to hit a wall is technical SEO, which often requires development skills, sustained time that gets squeezed out once a business gets busy, and competitive industries where the gap against full-time teams becomes hard to close without dedicated expertise. Search engines also change their ranking systems regularly, and staying current requires attention that is easy to lose when SEO is not the primary job.
A reasonable middle path for many businesses is handling content and basic optimization in-house while bringing in outside help for technical audits or more competitive strategy work, the areas where expertise and time matter most. That tends to be more cost effective than a full agency retainer while covering the gaps pure DIY effort struggles with.
A realistic DIY routine looks like this: checking Search Console weekly for new errors or sudden ranking drops, publishing one genuinely useful piece of content every week or two rather than sporadically, and doing a lighter technical check-in monthly instead of a full audit. That's a sustainable pace for a business owner without SEO as their primary job, and it covers the fundamentals that tend to matter most for a smaller, less competitive market.
Knowing when to bring in outside help isn't a failure of the DIY approach, it's recognizing where the return on an expert's time outweighs the cost, especially once competitors start investing seriously. The businesses that get this balance right tend to treat outside expertise as a targeted investment, not a wholesale replacement for what they can handle in-house.
The honest answer depends on what "SEO" means for your specific situation. The mechanical, one-time technical basics — fixing broken links, writing proper title tags and meta descriptions, submitting a sitemap, setting up Google Search Console — are learnable by a business owner with a few hours and a good guide, and don't require ongoing specialized expertise.
What's harder to DIY sustainably is the ongoing, strategic side: ongoing content strategy informed by real keyword research, technical SEO on a complex or custom-built site, and link building, which requires either genuine relationships or significant time investment to do credibly. Many businesses land on a hybrid: handling the basics in-house while bringing in outside help for the parts that require either specialized tools, ongoing time commitment, or expertise that takes years to build.