Best Marketing Agencies in Seoul (2026)

Introduction

The 12 marketing agencies below cover Seoul’s main routes to performance and growth work: listed digital groups, telecom-backed media reps, global media networks and smaller specialists for brands entering Korea. They were chosen for full-funnel or performance capability, recent activity and the strength of their client rosters.

Korean marketing runs on its own platforms. Naver’s share of domestic search reached about 64% in early 2026 on InternetTrend data, so Naver and Kakao fluency sits alongside Google, Meta and TikTok on most media plans. Group agencies such as Cheil Worldwide (Samsung), Innocean (Hyundai Motor Group) and HS Ad (LG) handle much of the chaebol spend, so much of the performance and growth work on this list comes from digital groups and specialists. FSN ranked in the Korea Advertising Federation’s top five by handled volume for a second year in 2026, and Bain Capital agreed a buyout of Echo Marketing at the end of 2025.

Every agency here has an active office in Seoul or Greater Seoul in 2026. The list is unranked, since the right choice depends on your channels, budget and how much of the funnel you want one partner to run. Creative-led network shops are on our advertising page and social specialists on our social media page.

The best marketing agencies in Seoul

1. kt nasmedia

KOSDAQ-listed, KT group · Gangnam · nasmedia.co.kr

kt nasmedia is a digital media and ad tech group founded in 2000. It became a KT affiliate in 2008 and changed its name from Nasmedia in 2025. It won Agency of the Year at the Agency Awards 2025 and was named a Naver Premier Partner for 2026, and it reports more than 4,800 clients and 394 staff.

Clients it names include Kering, Nexon, LG Electronics, Kia, Disney and Chanel. Much of its strength lies in inventory and data: it is the exclusive ad sales partner for Coupang Play, sold Netflix’s ad plan in Korea from 2023, and holds outdoor rights on several Seoul subway lines. Buyers who want a neutral planner should ask how recommendations are kept separate from those sales relationships.

2. Incross

KOSDAQ-listed, SK group · Gwanak-gu · incross.com

Incross, founded in 2007, is a media rep and ad tech company closely tied to SK Telecom and the wider SK ICT family. Its third-quarter 2026 results showed revenue of about KRW 15.2bn, up 16.6% on the year, with its advertising business up 20.3% on larger orders from major advertisers.

The offer spans media representation, performance marketing and commerce. Products include the Dawin video ad network, the ASUM marketing platform, which combines SK Telecom and SK ICT family ad businesses, the T deal commerce service for SK Telecom customers and Stellarise for AI product placement. It suits advertisers who want to reach SK Telecom audiences alongside standard digital buying.

3. Echo Marketing

Bain Capital buyout agreed December 2025 · Songpa-gu · echomarketing.co.kr

Echo Marketing is the closest thing on this list to a pure full-funnel performance shop. Founded in 2003 and listed on KOSDAQ in 2016, it covers strategy, creative with A/B testing, campaign optimisation, data analysis and CRM. It cites work in more than 56 countries, with offices in Seoul, Beijing and Singapore.

In December 2025 Bain Capital agreed to buy founder Kim Cheol-woong’s 43.66% stake, with a planned tender offer and delisting to follow, so ask who will lead your account after the change. Clients can hire it as an agency or through a “business boosting” model that combines investment with marketing. It was hiring across marketing, data, engineering and video in autumn 2026.

4. PlayD

KOSDAQ-listed, kt nasmedia subsidiary · Bundang (Seongnam) · playd.com

PlayD is an advertiser-side agency that began as N Search Marketing, joined Nasmedia in 2016 and listed on KOSDAQ in 2020. It now describes itself as an AI marketing partner, with campaign and media strategy, creative, performance marketing and its techHUB solutions under one roof.

Its 2026 work includes a seasonal campaign for K2, digital promotion for Hyundai Motor and an outdoor campaign for Salomon around the Seoul Half Marathon. Other clients include Amorepacific, Kia, Samsung C&T and SOCAR. The company has warned that impersonators are using its name and logo to solicit fees through blogs and messaging apps, so confirm any approach through its official site.

5. Wisebirds

Privately held · Pangyo (Seongnam) · wisebirds.com

Wisebirds is a digital marketing and ad tech company that reports KRW 579.2bn in 2025 execution volume and a team of about 530. With its subsidiary AdEfficiency it earned Google Premier Partner status in 2025, and it won Meta’s Performance Hero award at the Agency First Awards in 2024, its sixth consecutive win by its own count.

Coverage runs across search, display, video, app and shopping, with growing work in retail media. It says it was the first Korean firm selected for TikTok Marketing Partners, and it became an official agency for Daangn’s ad platform in 2024. A Tokyo subsidiary, Wisebirds Japan, serves e-commerce clients looking to sell in Japan.

6. FSN

KOSDAQ-listed · Gangnam · fsn.co.kr

FSN is a marketing group founded in 2007, with agencies including Adqua Interactive and Motherbrain, the Cauly mobile ad network and the brand-building business Boosters. Its 2025 handled volume of KRW 590.8bn placed it in the Korea Advertising Federation’s top five, and the company says that made it the largest agency outside the corporate in-house groups.

Adqua won 13 prizes at the Social i Awards in July 2026, for accounts including Disney+ Korea, Dunkin’, Baskin Robbins and Terra. Boosters shares revenue with partner brands, which sets the group apart from fee-only rivals. The group has also rolled out its own AI tools, including Adqua’s AIDE platform, across planning and production.

7. Dentsu Korea

Dentsu Group · Gangnam · dentsu.com

Dentsu’s Korean operation runs from JS Tower on Teheran-ro under six brands, including Carat, dentsu X, iProspect, Amplifi and Dentsu Creative. It has operated as Dentsu Holdings Korea since 2018. Deok Hee Kim, who earlier built GroupM into one of Korea’s largest media companies, was appointed chief executive in November 2023.

Recent listings for media buyers and CRM and digital experience planners show where the Korean business is investing. It describes client work across automotive, liquor, IT, luxury, sports, beauty and pharmaceuticals. It suits multinationals that want a global network’s media and performance tools with a local team; ask which of the six brands would hold your account.

8. WPP Media Korea

WPP · Seoul · wppmedia.com

WPP Media is WPP’s global media collective, formerly GroupM, bringing together agencies such as EssenceMediacom, Mindshare and Wavemaker with the Choreograph data business. Its Seoul team recruited in 2026 for senior roles including head of addressable media and senior media planning director.

The planning role leads a Seoul team working on one of the world’s largest technology companies, and it asks for depth in Korean media, social platforms, the Google Marketing stack and programmatic. This is the option for large international advertisers that buy media globally and want Korean execution inside that structure. Smaller accounts are likely to find better attention elsewhere on this list.

9. Asiance

Independent · Jung-gu · asiance.com

Asiance is a brand and technology agency launched in 2004, with its Seoul base in Jeong-dong and a presence in Japan. Its services combine strategy consulting, web, app and e-commerce builds, and marketing and data work including performance campaigns and AI video content. Campaign Asia-Pacific has recognised it in its Korea Digital Agency of the Year and Japan/Korea Independent Agency of the Year categories.

Clients include Dior, TUMI, Moët Hennessy, Aesop and Vacheron Constantin, and luxury is a clear strength. It published a Korea luxury consumer report and a review of brand performance on KakaoTalk in early 2026. It is a good fit for global premium brands that need the marketing and the customer experience handled together.

10. Inquivix

Privately held · Gangnam · inquivix.com

Inquivix works with global brands entering Korea, with services built around Naver SEO, Kakao marketing, paid media across Naver, Meta, Google and TikTok, and influencer programmes. It also handles market-entry strategy, localisation, PR and events, and it was publishing Korean market guidance through 2026.

Clients shown on its site include JW Marriott, Hyatt, the British Council, The Economist, Freshworks and TEMU. Hotel groups and B2B software firms feature heavily. Its published case figures are self-reported, so ask for references in your own sector.

11. InterAd

Privately held · Gangnam · interad.com

InterAd is a search specialist working since 2001, with roots as an official SEO vendor for Yahoo!. It offers global and Naver SEO, Japan SEO, search marketing, social media marketing, digital PR and analytics from its Teheran-ro office, and it is a Google Partner.

Clients it names include Philips, LVMH, Microsoft Korea, Samsung and Emirates. The team has been writing about AI search, including Google AI Overviews and Naver’s ADVoost, through 2026. It suits organic growth briefs and Korean companies building search visibility abroad.

12. DISRUPT

Privately held · Seongsu-dong · disrupt-global.com

DISRUPT is an e-commerce growth agency that helps brands expand internationally, mainly on Amazon, Shopify and Shopee. Services include Amazon account management and PPC, Meta, TikTok and Google ads, influencer programmes, email and content production, along with optimisation for AI search tools.

Its client list leans towards K-beauty and consumer brands, including COSRX, Biodance, Torriden, Olive Young and InBody. Results quoted on its site are self-reported or come from client testimonials. Korean brands selling overseas are the natural fit.

What to look for in a Seoul marketing agency

Start with platform depth. Naver search, Naver GFA, Kakao BizBoard and Coupang behave differently from global channels, and Korean plans usually mix all of them. Ask for examples on the exact platforms you will use, along with the agency’s partner status with each one.

Look closely at ownership, as it affects media advice. kt nasmedia and PlayD sit within the KT group and Incross is tied to SK, which gives them useful data and inventory along with commercial interests in particular channels. Network offices bring global trading terms and may follow global client mandates. It is reasonable to ask how each recommendation is made and which margins or rebates apply.

Agree the measure of success before any media is bought. Many Seoul agencies now promote in-house AI tools, and several publish strong return figures on their own sites. Ask how attribution works across Naver, Kakao and app or commerce data, who owns the ad accounts and data, and what happens to them if the relationship ends.

Performance work also produces a large volume of creative: video variants, banners, landing pages and weekly reports, often in Korean and English. Look at how the agency stores those files, gathers client feedback and tracks approvals, because a slow round of comments can delay a test by a week. A single place for the latest versions makes multi-market campaigns much easier to run.

How Fabric helps marketing agency teams

Fabric gives an agency one workspace for its files, client feedback and team knowledge, with AI search across all of it. The setup for performance marketing agencies suits firms running many accounts at once, with briefs, creative variants, reports and call notes kept together for each client.

Video and image variants live in Fabric’s cloud drive, which streams files on demand so they take no local disk space. Search works by meaning across documents, images and transcribed audio and video, as well as connected apps such as Google Drive, Notion and Gmail. Colour search helps when a team needs an earlier asset in a particular brand shade.

Creative review runs through shared links. Share a file or folder with a client as a commenter, with no sign-up needed, and they can leave timestamped comments on video and audio, draw on a video frame or an image, and highlight text in a PDF or document. The team then marks each comment completed, so a round of feedback works as a checklist.

For finished reports and decks, any file or folder can be published as a web page. Published links are view-only, with optional download, and take no comments, which keeps them clean for final delivery. Password protection is available, and link analytics shows when each named recipient opened a link and how long they spent with it.

On Team plans, self-writing docs can maintain a page for each client from meetings, Slack and the workspace, covering decisions, deliverables and open items. Fabric uses AES-256 encryption and holds CASA Tier 2; whether a setup meets a particular client’s data requirements is a question for that client’s legal and security teams.

Password protection and link analytics are included on Pro and Team plans, and self-writing docs on Team plans. See plans for teams.

Frequently asked questions

What is the best marketing agency in Seoul?

The right agency depends on the channels and markets involved. On 2025 and 2026 evidence, FSN reported the largest handled volume among agencies outside the corporate in-house groups, kt nasmedia was named Agency of the Year at the Agency Awards 2025, and Wisebirds earned Google Premier Partner status in 2025.

Which Seoul agencies suit a foreign brand entering Korea?

Inquivix is built around market entry and Korean platforms. Asiance has a long record with global luxury brands, and InterAd has worked on search for international companies since 2001. Larger multinationals may prefer Dentsu Korea or WPP Media Korea, particularly where media is bought under a global contract.

Which agencies help Korean brands sell overseas?

DISRUPT focuses on Amazon, Shopify and Shopee for brands expanding abroad, with a strong K-beauty client list. Echo Marketing cites work in more than 56 countries, and Wisebirds has a Tokyo subsidiary for e-commerce clients targeting Japan. InterAd offers overseas and Japan SEO.

What is happening with Echo Marketing?

Bain Capital signed an agreement in December 2025 to buy founder Kim Cheol-woong’s 43.66% stake, valuing the whole company at about KRW 500bn, with a tender offer and delisting planned to follow. Echo Marketing continued to recruit across marketing, data and technology roles in autumn 2026.

How does a marketing agency differ from an advertising agency in Seoul?

Marketing agencies on this list focus on media, data and measurable growth across the funnel, often with their own ad tech. Campaign-led creative work usually sits with the firms on our list of advertising agencies in Seoul, and some brands hire one of each.

Related lists

Marketing agencies in other cities: New York · London · Los Angeles · Singapore · Sydney

More in Seoul: Creative agencies · Advertising agencies · Social media agencies · Branding agencies · UX design agencies · Content studios

Run your agency on Fabric: Fabric for marketing teams · Fabric for agencies · Best client portal tools