A Practical Guide to Using UGC and
Influencers in Ads in Japan:
Stealth Marketing Rules, Backlash Risk and the "Find Winners with UGC → Then Influencers" Approach
When running vertical video ads in Japan, many overseas companies assume that "hiring Japanese influencers will drive sales faster." In Japan, however, stealth marketing has been regulated by law since October 2023, and there are also risks tied to individuals, such as online backlash. In this article, ZVA, which has produced vertical video and run ad campaigns in Japan and overseas, explains the practicalities of using UGC (videos styled like ordinary user content) and influencers in ads in Japan, covering market data, the key points of the stealth marketing regulation, each platform's disclosure rules, and the approach ZVA recommends: "find winning formats with UGC first, then move to influencers."
Key takeaways
- Japan's influencer marketing market was ¥86 billion (2024) and is projected to grow to ¥164.5 billion by 2029
- However, working with influencers comes with management overhead, the stealth marketing regulation (where the advertiser bears responsibility), and risks tied to individuals such as backlash. Only 20.3% of consumers trust influencer posts
- Burying "#PR" among a large number of hashtags, or showing it only in the middle or at the end of a video, is deemed insufficient under the stealth marketing regulation's operational standards
- ZVA recommends first testing 30+ patterns with UGC-style vertical videos to find a winning format, then, if needed, hiring influencers using the winning script
Influencer marketing is growing, and vertical video ads are growing even faster
Source: Cyber Buzz / Digital InFact (November 2024)
Source: CyberAgent / Digital InFact (March 2026)
Both charts use the same scale (max ¥564.8 billion). Because the research firms and base years differ, growth rates are for reference only. Hatched bars are forecasts.
According to research by Cyber Buzz and Digital InFact, Japan's influencer marketing market was ¥86 billion in 2024 (116% of the previous year) and is projected to reach ¥164.5 billion by 2029 (about 1.9 times the 2024 level). The overall social media marketing market is also expected to grow from ¥1.2038 trillion in 2024 to ¥2.1313 trillion in 2029.
Growing even faster, however, are vertical video ads. In research by CyberAgent and Digital InFact, the vertical video ad market was ¥204.9 billion in 2025 (155.9% of the previous year) and is expected to expand to ¥564.8 billion by 2029 (about 2.8 times the 2025 level). It exceeds influencer marketing in both market size and growth rate.
Influencer programs are growing too, but the main battleground for advertising in Japan is vertical video ads, which are expanding even faster. The realistic approach is to think about how to use influencers within vertical video advertising.
That said, using influencers in ads comes with challenges particular to Japan.
Three reasons working with influencers is difficult
1. Heavy management overhead
Each influencer requires coordination, from finding candidates and negotiating terms to reviewing scripts and shoot content, checking posts in advance, and enforcing disclosure rules. The more people involved, the heavier the management burden.
2. Risk of violating the stealth marketing regulation
Since October 1, 2023, content that hides the fact that it is advertising (stealth marketing) has been regulated under the Premiums and Representations Act. The advertiser bears responsibility, not the influencer who posted. Details are explained in the next section.
3. Risks tied to individuals, such as backlash
An influencer's past statements or events in their private life can cause the product or brand they promote to face criticism as well. In a tally by the Digital Crisis Research Institute, 38.2% of the 178 backlash incidents in January 2026 involved celebrities. The institute advises checking past posts before engagement and agreeing in advance on post content and how to respond if problems arise.
Source: Consumer Affairs Agency, "2026 Consumer White Paper" (Basic Survey on Consumer Awareness, N=5,473). Total of "trust very much" and "trust somewhat."
Moreover, only 20.3% of Japanese consumers trust posts by celebrities or influencers, half the rate for reviews by ordinary consumers (40.9%). However, younger generations tend to trust them more: 44.7% among those in their late teens and 38.8% among those in their 20s (Consumer White Paper).
Hiring an influencer doesn't automatically mean sales. Because you take on overhead, regulatory and backlash risk, precision in which script you use and what you have them say matters.
Key points of the stealth marketing regulation
Here are the points advertisers need to know, summarized from the Consumer Affairs Agency's "operational standards."
- Clearly stating "advertisement," "promotion," "sponsored" or "PR"
- Stating in text that "I received this product from Company A and am posting about it"
- In videos, showing the disclosure at a position and time viewers will notice, such as the opening
- Burying "#PR" among a large number of hashtags
- Showing it only for an instant in a video, or only in the middle or at the end of a long video
- Placing it where it is hard to see: small text, faint color, or at the very end of a post
- Writing "advertisement" but negating it with "these are my impressions as a third party"
- Covered even without explicit instructions: If the advertiser is in a position to determine the post's content and, viewed objectively, the post cannot be considered the poster's free will, it is treated as the advertiser's representation. This is judged from the content of communications, compensation, and past and future relationships
- Employee posts may also be covered: Posts by executives, managers and staff involved in sales promotion
- Be careful with "customer testimonials" on your own site too: If they are presented as third-party impressions, you must disclose that you requested them
This article is intended as general information and is not legal advice. For whether a specific disclosure is acceptable, consult a professional or the Consumer Affairs Agency's operational standards and Q&A.
Disclosure mechanisms by platform
| Platform | Disclosure mechanism | Key points |
|---|---|---|
| TikTok | Turning on the commercial content disclosure setting automatically labels the post as branded content | The promoted product must be identifiable in the video. Weight loss, pharmaceuticals, cosmetic surgery, certain financial products and more are prohibited categories (Branded Content Policy, effective August 31, 2026) |
| YouTube | Selecting the paid promotion setting displays a disclosure label at the start of the video | Legal compliance is the responsibility of the creator and their partner |
| A label showing the brand partnership (Paid partnership) can be added | Used with a business or creator account |
Note that videos the advertiser runs as ads, labeled "Ad" or "Sponsored" by the platform, are clearly the advertiser's representation. On the other hand, when content is posted from the influencer's own account like a regular post, the disclosures above are essential.
ZVA production and campaign services
Find your winning format first, with UGC-style vertical video
ZVA produces UGC-style vertical videos with Japanese talent in-house at volume and uses delivery data to find winning script patterns. From ¥50,000 per video (overseas projects quoted individually).
See pricing and process →ZVA's recommendation: find winning formats with UGC, then move to influencers
What matters most for results is "a winning script" and "a winning video pattern." That's why, rather than jumping straight to influencers, ZVA recommends proceeding in the following order.
Why this order works
- Lower risk: During testing, backlash and stealth marketing risk don't depend on an individual
- Better cost efficiency: You don't need to test "whether it works" with expensive influencers
- More concrete briefs for influencers: Because you can hand over data-proven script patterns, the content can drive results while still drawing on the influencer's personality
TikTok's internal analysis also found that ads featuring creators achieved a 70% higher click-through rate and 159% higher engagement than ads without them (compared at the same cost per 1,000 impressions; February 2024 to January 2025, TikTok research). The strength of vertical videos with a person speaking can be captured with UGC-style videos as well. For how to write scripts for Japan, see our practical guide to localizing vertical video ads for Japan.
First use UGC-style videos to learn from data "what to say, and how, to win." Influencers are an option for scaling that winning format further.
Pre-engagement checklist
| Check item | Why |
|---|---|
| Do you know your winning script patterns? | Hiring without knowing means paying to test |
| Have you decided how to disclose that it's an ad? | The position, timing and wording of the disclosure must be decided under the advertiser's responsibility |
| Will you use the platform's disclosure settings? | Each platform has its own mechanism, such as TikTok's disclosure setting or YouTube's paid promotion setting |
| Have you checked past posts and statements? | Prevents backlash caused by the individual from spreading to your brand |
| Have you decided how to respond if problems arise? | Agree in advance on post takedowns, communication channels and public statement policy |
| Does your product fall into a platform's prohibited or restricted categories? | Pharmaceuticals, cosmetic surgery, certain financial products and more cannot be branded content in the first place |
Summary
Japan's influencer marketing market continues to grow, but working with influencers carries risks particular to Japan: management overhead, the stealth marketing regulation and backlash. The share of Japanese consumers who trust influencer posts is also not high, at 20.3%.
That's exactly why the shortcut is to first test 30+ patterns with UGC-style vertical videos and find a winning script. Those videos alone can deliver solid results, and when you want to borrow reach, hiring influencers based on the winning script lets you drive results while keeping risk down. ZVA handles everything end to end in Japanese, English, Korean and Chinese, from producing UGC-style vertical videos with Japanese talent at volume to script design with influencer engagement in mind and ad campaign management.
References and sources
- Cyber Buzz / Digital InFact: Influencer marketing market survey (November 7, 2024) (Japanese)
- CyberAgent, "2025 Domestic Video Advertising Market Survey" (March 9, 2026) (Japanese)
- Consumer Affairs Agency: Stealth marketing regulation page (Japanese)
- Consumer Affairs Agency: Operational standards for the stealth marketing designation (March 28, 2023) (Japanese)
- Consumer Affairs Agency: Q&A on stealth marketing (Japanese)
- Consumer Affairs Agency: Enforcement of the Premiums and Representations Act in FY2025 (published May 28, 2026) (Japanese)
- Consumer Affairs Agency: Cease-and-desist order against a medical institution (published June 7, 2024) (Japanese)
- Web Tantousha Forum (June 11, 2024): Article on the first cease-and-desist order under the stealth marketing regulation (Japanese)
- Consumer Affairs Agency, "2026 Consumer White Paper," Part 1, Chapter 2 (Japanese)
- Siemple (Digital Crisis Research Institute): January 2026 backlash report (Japanese)
- TikTok Branded Content Policy
- YouTube Help: Paid product placements and endorsements (Japanese)
- Instagram Help: Branded content
- TikTok for Business blog, "The Creator Advantage" (November 24, 2025)
Figures are as of each source's publication date (checked October 2026). TikTok's creator ad data is TikTok's internal analysis. Because backlash-incident counting methods may differ from year to year, we do not compare across years. Statements about laws and regulations are not legal advice.