Calculate SEO Plugin Costs for Five, Twenty, and Fifty Client Sites

To compare SEO plugin costs across a client portfolio, apply each vendor’s site-counting rule to your site count, then calculate the first year and the renewal year separately. The table below does that for 5, 20, and 50 client sites using the list prices each vendor displayed on September 27, 2026. Prices change often, and several vendors run introductory offers, so rerun the numbers on the day you buy.

Two limits on this comparison. It covers license price only, not migration labor or the value of features that differ between plans. And it assumes every site needs the paid tier, which may not be true; see the section on free versions below.

How each vendor counts sites

Every figure here comes from the vendor’s own page, checked September 27, 2026. Where a vendor showed a price excluding tax, we say so.

Yoast SEO Premium. $118.80 a year excluding VAT, and “one subscription covers one site or domain.” The product page says agencies with fewer than 100 client sites get bulk discounts and that 100 or more have custom licensing. Yoast SEO Premium product page, checked September 27, 2026. Yoast’s help page lists the discounts for subscriptions bought in the same order: 5% from 5, 15% from 10, 20% from 25, 25% from 30, 30% from 40, and “Let’s talk!” from 50. Yoast’s help on using the plugin on multiple sites, checked September 27, 2026. Neither page states a different renewal price, or whether the bulk discount applies at renewal.

Rank Math. The pricing page displayed euros to our request, excluding VAT, billed annually. PRO covers “unlimited websites that you own. Client websites are excluded.” Business was €22.99 a month (€275.88 for the first year), renewing at €27.99 a month (€335.88 a year), for 200 client websites under a current offer, previously 100. Agency was €52.99 a month (€635.88), renewing at €64.99 a month (€779.88), for 750 client websites under the offer, previously 500. Rank Math pricing page, checked September 27, 2026. The page showed only euro prices when checked, so the Rank Math figures below stay in euros; check your checkout currency.

AIOSEO. With the page’s currency set to US dollars: Basic $49.50 (normally $99.00) for 1 site, Plus $99.50 (normally $199.00) for 3, Pro $199.50 (normally $399.00) for 10, and Elite $299.50 (normally $599.00) for 100. The page states “Special introductory pricing, all renewals are at full price” and “All pricing is in USD.” Its FAQ says client sites can be covered by a Pro or Agency license or by a license per client site. AIOSEO pricing page, checked September 27, 2026.

SEOPress PRO. $49 a year for 1 site, $59 for 5 sites, and $149 for unlimited sites, each marked “Renew at same price,” excluding tax. SEOPress pricing page, checked September 27, 2026. Its terms allow a license on clients’ websites when you are “directly involved in the creation, development, and active management of the site on their behalf.” SEOPress terms and conditions, checked September 27, 2026.

WP Visibility. $99 a year for unlimited sites, client sites included, renewing at $99 a year. WP Visibility pricing, checked September 27, 2026.

The arithmetic at five, twenty, and fifty sites

For each vendor we chose the smallest single plan that covers the site count and permits client sites. Rank Math is in euros; everything else is in US dollars. Do not add the columns across currencies.

How the Yoast figures were calculated:

• 5 sites: 5 × $118.80 = $594.00, less 5% = $564.30.
• 20 sites: 20 × $118.80 = $2,376.00, less 15% (the 10+ tier) = $2,019.60.
• 50 sites: 50 × $118.80 = $5,940.00 before discount. At 50 the help page replaces the discount with “Let’s talk!”, so the actual figure is whatever Yoast quotes.

For AIOSEO at 5 sites, a Plus license plus two Basic licenses would also cover five sites at $99.50 + $49.50 + $49.50 = $198.50 for the first year, and $199.00 + $99.00 + $99.00 = $397.00 at renewal. That is close to the Pro figure and means managing three licenses instead of one. Confirm with AIOSEO first that a three-site Plus license may cover client sites, since its FAQ names “the Pro / Agency license” or “an appropriate license for each client site.”

Taxes are excluded where the vendor said so, and the vendor’s checkout decides the final amount.

Separate first-year prices from renewals

A first-year offer tells you what the portfolio costs this year. The renewal price tells you what it costs every year after, which is the figure to budget for a roster you intend to keep.

• AIOSEO’s displayed prices are introductory, and its page says renewals are at full price, roughly double the first year in the table above.
• Rank Math shows a discounted first year and states the renewal price beside each plan. The larger client site allowances are also labeled as an offer, so confirm the allowance that applies to your renewal.
• SEOPress marks each plan “Renew at same price.” Its pricing FAQ adds exceptions for special promotions and says automatic renewal should be left on.
• Yoast’s pages do not state a separate renewal price or whether volume discounts carry into year two. Ask before budgeting year two.
• WP Visibility renews at the same $99, per the pricing page.

Plans also differ in what they include. Rank Math’s plans include keyword tracking allowances, AIOSEO’s include AI credits, and Yoast’s product page says Premium now includes its Local SEO plugin. A lower price for your site count is not a better fit if you need something only a pricier plan includes. The comparison page covers documented capabilities.

Not every site needs a paid plan

A portfolio calculation often assumes every site gets the premium tier. Check that first. Several vendors publish a free plugin; SEOPress’s pricing page, for example, describes SEOPress as freemium with a free release on WordPress.org. A small brochure site with no redirects and simple metadata may run well on a free tier, and moving it to a paid plan only adds cost.

Also check the terms that decide which sites a plan may cover. Rank Math’s PRO plan excludes client websites, so an agency’s client roster falls under Business or Agency. Yoast counts per site or domain, with its own rules for multisite. Get these wrong and the calculation describes a license you are not permitted to use.

Requirements are a cost too. WP Visibility needs WordPress 7.0 and PHP 8.1 or newer, per its install documentation, so a site on older versions needs an upgrade before it can count toward any saving.

Price the migration labor separately

License price is one line. Moving an existing site to a different plugin is labor: importing supported fields, re-entering settings that do not import, recreating redirects, and checking output. That labor happens once per site and can outweigh several years of license difference on a small roster.

Keep it as a separate line with its own driver. An illustrative formula:

switch cost for the portfolio =
  (sites to migrate) × (measured hours per site) × (your loaded hourly cost)
  + one-off setup and documentation time

Use hours you measured on a pilot site, not an estimate. Estimating a migration before quoting a fixed fee explains how to get that measurement.

Build your own calculator

1. List your sites and mark which genuinely need a premium plan.
2. For each vendor, read the site-counting rule and client-site terms on its own page.
3. Record the first-year and renewal prices, the currency, and whether tax is included, with the date you checked.
4. Calculate year one and year two separately for your actual site count.
5. Add migration labor as its own line for any site that would change plugin.
6. Recheck prices on the day you buy.