We’ve prepared this guide to help you understand better what an SEO agency delivers, what services you can pay for when collaborating with such agencies, and what to expect when hiring them. By the end, you’ll know exactly what you're buying before you sign a contract.

Core SEO services

Technical SEO Audit and Implementation

A technical SEO audit is a systematic review of your website's infrastructure to identify issues that prevent search engines from crawling, indexing, or ranking your pages. The deliverable is a prioritized report of fixes covering site speed, mobile usability, crawl errors, duplicate content, and structured data. Most agencies produce the audit report; whether they implement the fixes themselves or hand off a task list to your developer depends on the retainer tier.

A full technical audit for a small-to-midsized website typically takes two to four weeks and is often completed once at the start of an engagement, with quarterly rechecks.

On-Page Optimization

On-page optimization is the process of adjusting existing page content and HTML elements, including titles, meta descriptions, headers, internal links, and body copy, to better match search intent and ranking signals. The deliverable is a set of revised or newly written page elements, applied directly to your site or delivered as a document for your team to implement. Keyword research is almost always included; copywriting services for net-new pages may or may not be.

On-page optimization translates audit findings and keyword data into concrete changes that move rankings.

Keyword Research and Content Strategy

Keyword research is the identification of terms and questions your target audience types into search engines, mapped to the pages or content pieces best positioned to capture that traffic. The deliverable is usually a keyword map, i.e., a spreadsheet or document assigning priority keywords to specific URLs or planned content.

A thorough keyword map for a midsize site covers 100–500 terms and takes one to three weeks to produce.

A strong content strategy built on keyword research tells you exactly what to publish and why, not just what ranks now, but also what builds authority over time.

Link building is the process of earning or acquiring hyperlinks from other websites back to yours, which search engines treat as a signal of authority and trust. Some agencies provide monthly reports of new links acquired, while others offer detailed outreach logs and prospect lists. Link quality varies; placements on authoritative, topically relevant sites are worth far more than high-volume, low-quality directories.

Link building is the primary lever for improving rankings in competitive markets where on-page factors are roughly equal across competing sites.

Reporting and Analytics

Reporting is the ongoing measurement and communication of SEO performance, including rankings, organic traffic, conversions, and technical health, delivered on a monthly or quarterly basis. Every agency engagement should include a clear report tied to the goals you agreed on at the start, instead of vanity metrics. Google Analytics and Search Console access should be set up in your own accounts, not the agency's.

Monthly reports from reputable agencies include ranking movement for tracked keywords, traffic trends by page, and a prioritized action list for the next period.

Additional and optional services SEO companies offer

Content Production

Some agencies write and publish content on your behalf, including blog posts, landing pages, and resource guides, as part of the retainer. Many SEO agencies produce strategy and content briefs but expect your internal team or a separate content agency to write the actual copy.

Local SEO

Local SEO is optimization specifically for location-based searches. It includes Google Business Profile management, local citation building, and review strategy. It is a distinct discipline from national or eCommerce SEO and is typically offered as a separate service or retainer tier.

International and Multilingual SEO

Hreflang implementation (an HTML attribute that tells Google which language and country version of a page to show to a user when you have multiple versions of the same content for different languages or countries), country-specific keyword research, and international site architecture are specialized services that agencies don’t usually include in most standard retainers. If you operate in multiple countries or languages, confirm that the agency has direct experience with international SEO before engaging.

What SEO agencies DO NOT do

An SEO agency is not a paid media agency, so it doesn’t manage Google Ads, Meta campaigns, or programmatic spend. It is also not a full-service web development team. SEO agencies can flag technical issues and sometimes fix them, but large-scale site rebuilds belong with a development agency. SEO companies do not handle social media content strategy, email marketing, or PR, even though those disciplines can influence SEO indirectly. If you need those services, you need separate specialists.

How to tell if an agency's services match your needs

Before you request a proposal, be specific about your needs. Ask yourself:

  • What is your actual goal? More traffic, more leads, or better rankings for specific terms?
  • Do you have existing content and a functioning site, or are you starting from scratch?
  • Who on your team will act on agency recommendations?
  • What is your timeline for results?

These questions are important to ask because:

  • Each goal implies a different mix of services and a different timeline for results.
  • Established sites need optimization, while new sites need architecture, content production, and authority building simultaneously.
  • If you have no developer and no content writer in-house, you need an agency that implements, not just advises.
  • Most SEO campaigns show meaningful ranking movement in three to six months and material traffic impact in six to twelve months. If you need leads in thirty days, SEO is not the right channel to lead with.

Ready to find an SEO company that matches your exact needs? Browse DesignRush's SEO company directory — filter by budget, specialty, and client reviews.