Blog commenting means posting responses on other people's blog posts, often including a link back to your own site in the comment form's URL field or within the comment text itself. This was a popular link-building tactic from roughly 2005–2012, but its effectiveness has declined sharply because most platforms now automatically apply nofollow attributes to comment links, meaning they pass no PageRank. The direct SEO benefit today is minimal to nonexistent. Google's algorithms can easily identify comment spam, and mass blog commenting can trigger manual penalties if it looks manipulative. CommentLuv and similar plugins that rewarded commenters with dofollow links were heavily abused, so most serious publishers disabled them years ago. That said, strategic blog commenting still has indirect value when approached correctly. Leaving a thoughtful, relevant comment on a high-traffic industry blog can drive qualified referral traffic if other readers find it useful and click through. It positions you as someone engaged in the community, which can lead to genuine relationships with other bloggers, guest post opportunities, or natural mentions down the line. At Ottawa SEO, we never use blog commenting as a standalone link-building method. If a team member comments on an industry blog, it's because they have something genuinely useful to add to the conversation, not because we're chasing a backlink. The ROI simply doesn't justify dedicated time for comment campaigns compared to creating linkable content, digital PR, or outreach for editorial placements. Watch out for blog comment services or tools that promise to post hundreds of comments automatically. These are pure spam, easily detected, and risk associating your domain with low-quality practices. If you comment at all, do it manually, add real insight, and don't expect SEO gains. Treat it as networking, not link building, and you won't be disappointed when the nofollow links show up in your backlink profile with zero impact on rankings.