When one website links to another, it passes a signal of trust and relevance — what Google's founders originally called a "vote". The more votes a page receives from authoritative, relevant sources, the more likely Google is to rank it highly for relevant queries. This is the core principle behind link building, and it has remained central to Google's algorithm since PageRank was first described in 1998.
The practice has evolved considerably. Early link building relied on volume — acquiring as many links as possible regardless of source. Google's Penguin algorithm (2012) and subsequent updates shifted the calculus decisively toward quality: a small number of links from genuinely authoritative, relevant sources now outperforms a large number of low-quality links. Manipulative link schemes risk manual penalties and algorithmic suppression.
For London businesses competing in sectors where organic search drives significant revenue — professional services, healthcare, finance, legal, ecommerce — a sustainable link building strategy is one of the highest-ROI SEO investments available.
Why Backlinks Remain a Primary Ranking Signal
Despite the evolution of Google's algorithm — the introduction of RankBrain, BERT, MUM, and increasingly sophisticated entity understanding — backlinks have consistently remained among the top three ranking factors. Google's own documentation confirms that links help Google discover new pages and understand how pages relate to each other.
Authority Transfer
Links from high-authority domains pass PageRank to the linked page, increasing its authority in Google's model.
Topical Relevance
Links from topically relevant sources signal to Google that the linked page is a credible resource within a specific subject area.
Trust Signals
Links from established, trusted publications (news outlets, academic institutions, government sites) are strong trust signals that are difficult to replicate artificially.
Types of Links: Quality Spectrum
From highest to lowest value — and one to avoid entirely.
Editorial Links
HighestLinks earned naturally when another website references your content as a source, cites your research, or recommends your business. These carry the most authority because they are given voluntarily by a third party.
How to earn / avoid
Produce genuinely useful, original content — data studies, original research, comprehensive guides, or expert commentary that journalists and bloggers want to reference.
Digital PR Links
Very HighLinks earned through proactive outreach to journalists and publications — pitching data-driven stories, expert commentary, or newsworthy content that earns coverage and links in return.
How to earn / avoid
Develop a digital PR strategy: identify link-worthy angles in your business data, pitch to relevant publications, and respond to journalist requests via HARO or Connectively.
Resource Page Links
HighLinks from curated resource pages — pages that list the best tools, guides, or services in a category. These are actively maintained by webmasters and carry genuine editorial intent.
How to earn / avoid
Identify resource pages in your industry, create a resource that deserves inclusion, and reach out to the page owner with a specific, relevant pitch.
Guest Post Links
Medium–HighLinks earned by contributing original articles to other websites in your industry. Quality varies significantly — links from relevant, authoritative publications are valuable; links from low-quality 'guest post farms' are not.
How to earn / avoid
Target publications your target audience actually reads. Pitch genuinely useful content, not thinly veiled promotional articles.
Business Directory Links
Low–MediumLinks from business directories — Yell, Thomson Local, Yelp, and industry-specific directories. These have limited ranking impact individually but contribute to citation consistency and local SEO.
How to earn / avoid
Build citations on Tier 1 and industry-specific directories as part of a local SEO strategy. Do not rely on directories as a primary link building tactic.
Toxic / Spammy Links
NegativeLinks from link farms, PBNs (private blog networks), irrelevant foreign directories, or sites created purely for link selling. These can trigger manual penalties or algorithmic suppression.
How to earn / avoid
Avoid entirely. Audit your existing link profile regularly and disavow toxic links using Google Search Console.
Link Metrics: What to Measure
Domain Authority (DA) / Domain Rating (DR)
Moz / AhrefsA 0–100 score estimating the overall authority of a domain based on its link profile. Higher is better, but relevance matters more than raw score.
Referring Domains
Ahrefs / SemrushThe number of unique domains linking to a page or site. More referring domains from diverse, relevant sources is a stronger signal than many links from few domains.
Anchor Text Distribution
Ahrefs / SemrushThe text used in links pointing to your site. A natural profile has varied anchor text — brand name, URL, generic terms, and some keyword-rich anchors. Over-optimised anchor text is a penalty risk.
Link Velocity
Ahrefs / SemrushThe rate at which new links are acquired over time. Sudden spikes in link acquisition can trigger algorithmic scrutiny. Consistent, gradual growth is the healthiest pattern.
Topical Relevance
Manual assessmentHow closely related the linking domain's topic is to your own. A link from a relevant industry publication is worth more than a link from an unrelated high-DA site.
Link Building for London Businesses: The Local Advantage
London businesses have access to a rich ecosystem of local link opportunities that businesses in smaller markets do not. These local links carry both authority and local relevance signals — making them particularly valuable for businesses targeting London-specific queries.
London Chamber of Commerce
Business association
High authority, strong local relevance
London Evening Standard / Time Out London
Local media
High authority, strong local relevance
London Business School / UCL / LSE
Academic institutions
Very high authority, strong trust signal
Greater London Authority
Government
Very high authority, strong trust signal
London borough council websites
Local government
Medium authority, strong local relevance
London-specific industry associations
Trade bodies
Medium–high authority, topical relevance
London startup and tech publications
Niche media
Medium authority, strong topical relevance
London event sponsorships
Events
Variable authority, local and topical relevance
Related Guides
Frequently Asked Questions
Are backlinks still important for SEO in 2026?
Yes — backlinks remain one of Google's strongest ranking signals. Google's own documentation and multiple industry studies confirm that the number and quality of backlinks pointing to a page is a primary factor in determining its position in search results. While the algorithm has evolved to weight link quality over quantity, the fundamental principle has not changed.
What is the difference between a dofollow and nofollow link?
A dofollow link passes PageRank from the linking page to the linked page — this directly influences rankings. A nofollow link includes the rel='nofollow' attribute. Since 2019, Google treats nofollow as a 'hint' rather than a directive, meaning some nofollow links may pass partial link equity. For link building purposes, dofollow links from relevant, authoritative sources are the primary target.
How long does link building take to show results?
Link building typically takes 3–6 months to produce measurable ranking improvements, though this varies by keyword competitiveness, current domain authority, and link quality. The cumulative effect of consistent link building over 12+ months is substantially greater than short-term campaigns.
What link building tactics should I avoid?
Tactics that violate Google's link spam policies include: buying or selling links that pass PageRank, participating in link exchange schemes, using automated programmes to create links, and building links with over-optimised anchor text at scale. These risk manual penalties or algorithmic suppression. The safest approach is earning links through genuinely useful content and digital PR.
Build Links That Actually Move Rankings
Our Link Building Services focus on editorial links, digital PR, and London-specific opportunities — the types of links that produce lasting ranking improvements.
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