{"id":81224,"date":"2026-10-01T10:29:18","date_gmt":"2026-10-01T10:29:18","guid":{"rendered":"https:\/\/www.arimetrics.com\/?post_type=encyclopedia&#038;p=81224"},"modified":"2026-10-01T11:05:40","modified_gmt":"2026-10-01T11:05:40","slug":"tacos-total-advertising-cost-of-sales","status":"publish","type":"encyclopedia","link":"https:\/\/www.arimetrics.com\/en\/digital-glossary\/tacos-total-advertising-cost-of-sales","title":{"rendered":"TACoS"},"content":{"rendered":"<p><img decoding=\"async\" class=\"boxpad alignright wp-image-81225 size-full\" src=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/10\/tacos.jpg\" alt=\"TACoS (Total Advertising Cost of Sales)\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/10\/tacos.jpg 300w, https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/10\/tacos-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/> <strong>Definition:<\/strong><\/p>\n<p><strong>TACoS<\/strong>, short for Total Advertising Cost of Sales, is a metric used on Amazon to relate advertising spend to total sales generated during a period. It is expressed as a percentage and its denominator includes both ad-attributed sales and sales without advertising attribution.<\/p>\n<p>TACoS shows how much of total revenue is represented by advertising spend. Its scope is broader than ACoS, but it <strong>does not measure profit<\/strong> or prove on its own that advertising caused sales without attribution.<\/p>\n\n<h2>TACoS formula and scope<\/h2>\n<p>The basic formula is <strong>TACoS:<\/strong> advertising spend \u00f7 total sales \u00d7 100. Amazon Ads also describes this metric as ad spend expressed as a percentage of total sales in its <a href=\"https:\/\/advertising.amazon.com\/en-gb\/library\/guides\/authors-guide-to-sponsored-products\" target=\"_blank\" rel=\"noopener\">Sponsored Products guide for authors<\/a>.<\/p>\n<p>For the calculation to be consistent, the numerator and denominator must cover <strong>the same period<\/strong>, marketplace, and commercial scope. The analysis can apply to an account, brand, product line, or ASIN, but spend from one set should not be compared with sales from another.<\/p>\n<p>The calculation requires three clearly defined components:<\/p>\n<ul>\n<li><strong>Advertising spend:<\/strong> the cost of the campaigns included in the analysis.<\/li>\n<li><strong>Attributed sales:<\/strong> revenue that the advertising system connects to ads.<\/li>\n<li><strong>Non-attributed sales:<\/strong> all other sales recorded within the same scope and period.<\/li>\n<\/ul>\n<p>If advertising spend is \u20ac2,000 and total sales reach \u20ac20,000, <strong>TACoS is 10%<\/strong>. This means that advertising costs equal ten euros for every hundred euros in total sales, without showing how much profit remains after other costs.<\/p>\n<h2>Interpreting changes over time<\/h2>\n<p>TACoS becomes more informative when it is viewed as a <strong>time series<\/strong> rather than as an isolated figure. Comparing equivalent periods shows whether advertising investment is growing at a different rate from overall sales.<\/p>\n<p>Its movement can follow several patterns:<\/p>\n<ul>\n<li><strong>Falling TACoS:<\/strong> total sales are growing faster than spend, or spend is falling faster than sales.<\/li>\n<li><strong>Stable TACoS:<\/strong> advertising investment and total sales maintain a similar relationship during the periods compared.<\/li>\n<li><strong>Rising TACoS:<\/strong> spend is growing faster than total sales, or sales are falling while investment remains steady.<\/li>\n<\/ul>\n<p>A decline may coincide with a larger share of non-attributed sales, but it <strong>does not prove causation<\/strong>. Price changes, seasonality, availability, promotions, brand demand, or differences in data scope may also explain it. Likewise, a temporary increase may reflect a product launch or a deliberate expansion in advertising coverage.<\/p>\n<h2>Relationship with ACoS and ROAS<\/h2>\n<p>TACoS, ACoS, and ROAS all connect advertising and revenue, but they represent <strong>three distinct scopes<\/strong>. The key distinction is whether attributed sales or total sales are considered.<\/p>\n<ul>\n<li><strong>TACoS:<\/strong> divides advertising spend by all sales within the scope analysed.<\/li>\n<li><strong><a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/acos-advertising-cost-of-sales\">ACoS<\/a>:<\/strong> divides advertising spend by sales attributed to ads.<\/li>\n<li><strong><a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/roas\">ROAS<\/a>:<\/strong> divides attributed sales or conversion value by advertising spend.<\/li>\n<\/ul>\n<p>If \u20ac2,000 in advertising spend generates \u20ac8,000 in attributed sales within total sales of \u20ac20,000, ACoS is 25%, ROAS is 4, and TACoS is 10%. <strong>ACoS and ROAS<\/strong> are inverse relationships when they use exactly the same data; TACoS is not, because it uses a broader denominator.<\/p>\n<p><strong>None replaces ROI<\/strong>. <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/roi\">ROI<\/a> includes the attributable profit or loss and the costs defined for the investment, whereas TACoS only relates advertising spend to total sales.<\/p>\n<h2>Factors that change the result<\/h2>\n<p>The percentage can move because of advertising decisions and because of business changes that do not originate in campaigns. Interpreting it requires reviewing <strong>both sides<\/strong> of the formula.<\/p>\n<ul>\n<li><strong>Budget and bids:<\/strong> affect spend, coverage, and the pace of participation in auctions.<\/li>\n<li><strong>Price and promotions:<\/strong> change sales value even when order volume remains the same.<\/li>\n<li><strong>Inventory:<\/strong> going out of stock can reduce both attributed and non-attributed sales.<\/li>\n<li><strong>Seasonality:<\/strong> changes demand and makes non-equivalent periods difficult to compare.<\/li>\n<li><strong>Catalogue:<\/strong> adding or removing products changes the sales base used in the calculation.<\/li>\n<li><strong>Measurement:<\/strong> returns, reporting delays, currencies, and time zones can produce differences between sources.<\/li>\n<\/ul>\n<p>TACoS often requires <strong>two sources to be combined<\/strong>: advertising data and seller or vendor sales information. Before using it as a <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/kpi\">KPI<\/a>, the campaigns, products, marketplaces, and adjustments included in the figure should be documented.<\/p>\n<h2>Limits when evaluating the business<\/h2>\n<p>A low percentage <strong>does not guarantee efficiency<\/strong> or profitability. It may coexist with low volume, lost market share, thin margins, or reduced spend that constrains future sales. A high percentage is not inherently negative either if it reflects a controlled launch or expansion.<\/p>\n<p>Profitability depends on the margin remaining after product costs, fees, fulfilment, discounts, returns, non-recoverable taxes, and other expenses. If every product had a consistent contribution margin, TACoS would show the share of that margin consumed by advertising; in a real catalogue, the product mix can make this approximation a <strong>misleading average<\/strong>.<\/p>\n<p>Non-attributed sales may also come from organic visibility, repeat customers, external activity, brand demand, or other <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/marketplace\">marketplace<\/a> channels. TACoS describes the relative dependence on advertising spend, but it <strong>does not isolate incrementality<\/strong>, causation, or profitability on its own.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Definition: TACoS, short for Total Advertising Cost of Sales, is a metric used on Amazon to relate advertising spend to total sales generated during a period. It is expressed as a percentage and its denominator includes both ad-attributed sales and sales without advertising attribution. TACoS shows how much of total revenue is represented by advertising [&hellip;]<\/p>\n","protected":false},"author":33,"featured_media":81227,"template":"","encyclopedia-tag":[1229,296],"class_list":["post-81224","encyclopedia","type-encyclopedia","status-publish","has-post-thumbnail","hentry","encyclopedia-tag-advertising-costs","encyclopedia-tag-metric"],"_links":{"self":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia\/81224","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia"}],"about":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/types\/encyclopedia"}],"author":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/users\/33"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media\/81227"}],"wp:attachment":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media?parent=81224"}],"wp:term":[{"taxonomy":"encyclopedia-tag","embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia-tag?post=81224"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}