SEO vs Social Media Ads: Results From 1,500+ Agency Case Studies

SEO and social media ads are often pitched as rivals for the same budget. One earns attention through search; the other buys it in the feed. Most comparisons stop at how the two work. Very few show what each one delivered for real clients.

This page compares them with data. It draws on 1,534 case studies from 66 marketing agencies in OpenServed's directory: 1,090 that list SEO, 525 that list social media ads, and 81 that list both. For the head-to-head we use the 301 case studies that list SEO alone and the 129 that list social media ads alone, because only those show one channel's results without the other mixed in.

Data as of October 2026. These are results agencies chose to publish, so they show what a successful campaign looks like, not what an average one does. If you cite a number, please cite the date.

SEO vs social media ads at a glance

• SEO-only case studies report a median 98% increase in conversions or leads; social-ads-only case studies report 67%.
• Revenue goes the other way: a median 128% increase for social-ads-only case studies against 105% for SEO-only ones.
• Across all case studies that list each channel, revenue gains are level: 110% for SEO and 106% for social media ads.
• Social ads case studies are more likely to prove a business result. 62% of social-ads-only case studies report revenue, leads or conversions, against 44% of SEO-only ones.
• A third of social-ads-only case studies report cost or ROAS. 35% show a cost per acquisition or lead and 32% show ROAS. For SEO-only case studies both are about 1% or less.
• 61% of SEO-only case studies report traffic and 44% report keyword rankings. For social-ads-only case studies the figures are 12% and 0%.
• SEO clients are smaller. Small businesses are 54% of SEO case studies and 34% of social media ads ones; enterprises are 10% and 30%.
• Manufacturers barely use social ads; food and beverage brands prefer them. SEO appears in 60% of industrial case studies and social ads in 7%. In food and beverage it is 26% and 34%.
• The data can't measure ROI or speed. Only 2 of the 1,534 case studies state a budget, and only 16 say how long the work took.

The short answer

Neither channel wins outright. SEO case studies report larger lead gains, and they dominate among small businesses and B2B industries. Social media ads case studies match SEO on revenue, are more likely to show what a result cost, and dominate among consumer brands and enterprises. Which channel fits depends on what you sell, how big you are and what you need to be able to measure. The last section of this page turns that into a choice.

What SEO and social media ads case studies report

Before comparing results, look at what each channel's case studies choose to show. The two are sold and proven in different ways.

SEO case studies report traffic; social ads case studies report sales and cost. Share of single-service case studies that include each result:

• Website traffic: 61% of SEO-only, 12% of social-ads-only
• Keyword rankings: 44% of SEO-only, 0% of social-ads-only
• Conversions or leads: 19% of SEO-only, 35% of social-ads-only
• Revenue or sales: 25% of SEO-only, 36% of social-ads-only
• Cost per acquisition or lead: 1% of SEO-only, 35% of social-ads-only
• ROAS: 0% of SEO-only, 32% of social-ads-only
• Engagement and reach: 1% of SEO-only, 22% of social-ads-only

Social ads case studies are more likely to show a business result. 62% of social-ads-only case studies report revenue, leads or conversions. For SEO-only case studies it is 44%.

Cost is almost never part of an SEO case study. 65% of social-ads-only case studies report an efficiency metric such as cost per acquisition or ROAS. Only 3% of SEO-only case studies do.

Impressions are the one result both report equally often, in 16% of each group. For SEO that means search impressions; for social ads it means ad impressions.

SEO vs social media ads results on shared metrics

Leads, conversions and revenue mean the same thing for both channels, so they can be compared directly. We show two views: single-service case studies, which are the cleanest, and all case studies that list each channel, which give a larger sample.

In single-service case studies, SEO leads on conversions and social ads lead on revenue. Median reported gain, with the middle half in brackets:

• Conversions or leads: 98% for SEO only (56% to 400%, 44 case studies), 67% for social ads only (38% to 149%, 23 case studies)
• Revenue: 105% for SEO only (55% to 260%, 67 case studies), 128% for social ads only (35% to 452%, 21 case studies)

Across all case studies, SEO still leads on conversions and revenue is level. Median reported gain, bundles included:

• Conversions or leads: 124% for SEO (60% to 300%, 221 case studies), 97% for social media ads (44% to 218%, 123 case studies)
• Revenue: 110% for SEO (50% to 296%, 227 case studies), 106% for social media ads (44% to 303%, 123 case studies)

The lead gap is consistent; the revenue gap is not. SEO case studies report larger gains in conversions and leads in both views. On revenue, social ads are ahead in the small single-service group, on only 21 data points with a very wide range, and level with SEO in the larger group. The safest reading is that the two are close on revenue.

Leads and conversions separately. Across all case studies, the median reported gain is 116% for SEO and 97% for social media ads on leads (142 and 53 case studies), and 137% and 96% on conversions (94 and 72 case studies).

This is not proof that SEO generates more leads than social ads. Three things sit behind the gap:

• Smaller clients. 64% of SEO-only clients with a known size are small businesses, against 50% of social-ads-only clients. Across the directory, small businesses report the largest gains in conversions or leads.
• Different industries. About half of social-ads-only case studies are for fashion, retail and food brands, which measure success in sales, not leads.
• A small social sample. The social-ads-only figures rest on 21 to 23 data points, and one agency supplies 38% of that group.

What each channel measures on its own

Some results exist for one channel only. They are shown side by side here, not as a contest. These figures come from all case studies that list each channel, and each links to its full breakdown.

SEO (SEO Statistics 2026):

• Organic traffic: median reported increase of 102% (462 case studies)
• Keyword rankings: median reported growth of 227% (173 case studies)

Social media ads (Social Media Ads Statistics 2026):

• Cost per acquisition or lead: median reported cut of 45% (79 case studies)
• ROAS: median reported increase of 49% (48 case studies); where agencies state the ROAS itself, the median is 8.0x (41 case studies)
• Engagement and reach: median reported gain of 132% (52 case studies)
• Click-through rate: median reported increase of 74% (35 case studies)

SEO vs social media ads by industry

No industry has enough single-service case studies for a clean comparison. This section uses every case study that lists each channel, bundles included, so a case study listing both counts on both sides. We merged industry labels into 13 groups (see methodology).

B2B industries rely on SEO; consumer brands use social ads as much. Share of each industry's case studies that list SEO and social media ads:

• Industrial & Manufacturing: 60% SEO, 7% social media ads
• Professional & B2B Services: 49% SEO, 7% social media ads
• Home, Property & Local Services: 48% SEO, 23% social media ads
• Software & Technology: 37% SEO, 12% social media ads
• Retail & Ecommerce: 44% SEO, 21% social media ads
• Healthcare & Wellness: 45% SEO, 23% social media ads
• Financial Services: 31% SEO, 15% social media ads
• Education & Nonprofit: 33% SEO, 19% social media ads
• Fashion, Beauty & Jewelry: 38% SEO, 33% social media ads
• Food & Beverage: 26% SEO, 34% social media ads

Manufacturers and B2B firms use SEO seven to nine times as often as social ads. In those two groups SEO appears in 49% to 60% of case studies and social media ads in 7%.

Food and beverage is the one large industry where social ads lead. Social media ads appear in 34% of Food & Beverage case studies and SEO in 26%. In Fashion, Beauty & Jewelry the two are close, at 33% and 38%.

Revenue gains for retail are nearly identical on both channels. The median reported revenue gain for Retail & Ecommerce clients is 107% for SEO (90 case studies) and 106% for social media ads (53 case studies). For Fashion, Beauty & Jewelry it is 120% for SEO (61) and 86% for social media ads (36).

Healthcare clients report large lead gains from both. The median reported gain in conversions or leads for Healthcare & Wellness clients is 195% for SEO (37 case studies) and 153% for social media ads (20 case studies). No other industry has 20 lead data points on both sides.

SEO vs social media ads by client size

This section also uses every case study that lists each channel, bundles included. Client size is the client's employee count.

SEO is a small-business channel; social ads are spread toward enterprise. Among SEO case studies with a known client size, 54% are small businesses (1 to 50 employees) and 10% are enterprises (more than 1,000). Among social media ads case studies, 34% are small businesses and 30% are enterprises.

The bigger the client, the closer the two get. Share of case studies at each client size that list SEO and social media ads:

• Small (1 to 50 employees): 55% SEO, 15% social media ads
• Medium (51 to 200): 43% SEO, 16% social media ads
• Large (201 to 1,000): 37% SEO, 19% social media ads
• Enterprise (1,000+): 18% SEO, 22% social media ads

Lead gains by size are mixed. The median reported gain in conversions or leads is 131% for SEO and 97% for social media ads among small businesses (83 and 35 case studies), 93% and 127% among medium businesses (43 and 24), and 173% and 82% among large businesses (35 and 21). Neither channel has 20 enterprise data points.

Small businesses report similar revenue gains from both. The median reported revenue gain for small businesses is 105% for SEO (125 case studies) and 92% for social media ads (32 case studies).

Enterprises use social ads for reach. An engagement, reach or awareness stat appears in 53% of enterprise social media ads case studies, against 24% of enterprise SEO case studies.

What happens when SEO and social media ads are combined

Few case studies combine these two. Only 81 list both SEO and social media ads. That is 7% of all SEO case studies and 15% of all social media ads case studies, and 64 of the 81 also list PPC.

Combined case studies report the largest lead gains. Median reported gain, with the middle half in brackets:

• Conversions or leads: 156% together (92% to 272%, 26 case studies), 98% for SEO only, 67% for social ads only
• Revenue: 100% together (51% to 216%, 21 case studies), 105% for SEO only, 128% for social ads only

Revenue gains are no higher when the two are combined. The combined group reports a median 100% revenue gain, slightly below either channel alone.

Combined case studies are the most likely to show a business result. 73% report revenue, leads or conversions, against 62% of social-ads-only and 44% of SEO-only case studies.

These figures rest on 21 to 26 data points, and most of the combined case studies run paid search as well. Read them as what agencies report from a multi-channel program, not as proof that the two channels multiply each other.

What the data can't tell you

It can't measure ROI. Only 2 of the 1,534 case studies state a budget. Without spend, there is no way to compare what each channel returned per dollar.

It can't measure speed. Only 16 case studies say how long the work took.

It only shows wins. Agencies publish their best work, and only 54 of the 1,534 case studies are Client-verified. Every number here is a published best case, not a typical outcome.

General context, not from this data: social ads can start producing clicks the day a campaign goes live, and stop when the spend stops. SEO usually takes months to build, and the traffic it earns doesn't end when a campaign does. The two also reach people at different moments: search reaches people already looking for something, while social ads reach people who weren't. Those differences matter for the choice below, but our case studies can't put a number on them.

SEO or social media ads: which should you choose?

The data doesn't pick a winner, but it does show where each channel has the stronger record.

• If you're a small business, SEO is the far more common choice. SEO is listed in 55% of small-business case studies and social media ads in 15%. Small businesses report a median lead gain of 131% from SEO and 97% from social ads.
• If you sell to other businesses, most of the evidence is for SEO. In manufacturing and B2B services, SEO appears seven to nine times as often as social ads.
• If you're a consumer brand selling online, either can work. Retail clients report nearly identical revenue gains from both, and fashion and food brands use social ads about as often as SEO.
• If you need to prove cost or return on ad spend, social ads have the proof. A third of social-ads-only case studies report cost per acquisition or ROAS. SEO case studies almost never do.
• If you're an enterprise looking for reach, social ads are the usual tool. Social ads appear slightly more often than SEO in enterprise case studies, and half of those report engagement or awareness.
• If you need results quickly, social ads are the usual answer. That comes from how the channels work, not from this data.
• If you can fund both, expect to run paid search too. Most case studies that combine SEO and social ads also list PPC, and that group reports the largest lead gains.

Whichever you choose, ask an agency for three things most case studies leave out: a business result, what it cost, and how long it took.

You can browse the case studies behind these numbers in OpenServed's SEO agency directory and social media ads agency directory, and filter by industry, client size and location. For the other common comparison, see SEO vs PPC.

Methodology

• Source: all 1,534 case studies in OpenServed's directory that list SEO, Social Media Ads or both, as of October 5, 2026, from 66 agencies: 1,090 list SEO, 525 list Social Media Ads and 81 list both. Each links to the agency's own published case study.
• Single-service comparison: the head-to-head uses the 301 case studies that list SEO as their only service and the 129 that list Social Media Ads as their only service. Bundled case studies can't show which channel produced a result.
• All case studies: because the single-service social group is small, we also show figures for every case study that lists each channel, bundles included. The industry and client-size sections use this larger group. A case study that lists both channels counts toward both.
• One set of rules for both channels: each case study carries the result stats the agency published, as free text. We assigned each stat to a metric by keyword matching, using the same rules for SEO and social media ads case studies.
• Percentages only: medians use stats that state a percentage change. Plain counts, dollar figures and before-and-after pairs are left out.
• Direction: cost metrics count reductions; every other metric counts increases. Comparisons with a goal, target or industry average are left out.
• One data point per case study: if a case study has several stats for the same metric, we use the first one listed. "Conversions or leads" uses whichever comes first.
• Median and middle half: we report the median, not the average, because a handful of gains above 1,000% would distort an average. The middle half is the range from the 25th to the 75th percentile.
• Minimum sample: we compare the two channels on a metric or segment only when both have at least 20 data points.
• Channel-specific figures: the organic traffic, keyword, cost, ROAS, engagement and click-through figures are quoted from our SEO and social media ads statistics pages, which exclude stats that name another channel.
• Industry groups: we merged industry labels into 13 groups. Client size uses employee count: small is 1 to 50, medium 51 to 200, large 201 to 1,000 and enterprise more than 1,000.
• Selection bias: agencies publish their wins, and the directory is not a random sample of the industry. Coalition Technologies supplies 25% of the SEO-only case studies and LYFE Marketing 38% of the social-ads-only ones.
• Agency-reported: except for the 54 Client-verified case studies, results are as published by each agency and haven't been independently confirmed.

Cite this data: OpenServed, "SEO vs Social Media Ads: Results From 1,500+ Agency Case Studies", October 2026, https://openserved.com/blog/seo-vs-social-media-ads