Lemontree

What Lemontree does

Lemontree Inc. (레몬트리), operating under the brand Firfin (퍼핀), is a South Korean fintech company that has built a vertically integrated family financial platform targeting children aged 7 and older and their parents. Founded in July 2021 by CEO Lee Min-hee, the company received an Electronic Financial Business license from Korea's Financial Services Commission in January 2023 and launched Firfin in March 2023. The core product is a prepaid debit card (issued without requiring a bank account or branch visit, via app-based phone authentication) that combines payment functionality at all KB Kookmin Card merchants nationwide with embedded Rail Plus transit card capability, barcode payments with up to 5% cashback, and a parent control dashboard supporting daily/monthly limits, instant and recurring allowance transfers, real-time transaction monitoring with photo capture, and remote card lock. The Firfin app is split into a parent app and child app, and is augmented by Firfin World — a gamified financial education content hub with 2,000+ economics and finance quizzes plus a $2,000 virtual US stock portfolio. More recent additions include Firfin Investment (parent-supervised stock trading via Shinhan Investment Securities CMA accounts, launched January 2026), Firfin Convenience Store (gifticon marketplace), Firfin Plus membership subscription, KFQA — Korea's first recognized children's financial literacy assessment co-developed with Maeil Business Newspaper — and Rich Pass (March 2026), an integrated family wealth service extending into minor stock account opening, proxy trading, gift tax planning, and Hometax self-filing.

Lemontree's business model is a freemium-plus-interchange combination. The core card and app are free (no issuance fee, monthly fee, or allowance transfer fee), driving rapid top-of-funnel acquisition (200,000+ users and 70,000+ cards within roughly a year of launch). Revenue is generated through (1) Firfin Plus subscription (monthly/annual access to premium content, with a 2026 refund policy tied to actual quiz usage at ₩2,000 per unit), (2) interchange share from card swipes and barcode payments processed via KB Kookmin Card, (3) gifticon sale margins in the Firfin Convenience Store, and (4) referral-program acquisition costs. The company has raised approximately ₩10.8 billion (~$8M) cumulatively across a 2021 seed round (₩5B from KB Investment, SpringCamp, Capstone Partners, TVT Partners, Base Investment, Fast Ventures, D.Camp) and a July 2024 Pre-Series A (₩2.3B led by Kakao Investment). Go-to-market is product-led: self-serve onboarding via Google Play, word-of-mouth, a friends-referral program paying ₩2,000 in Firfin points per invite, and co-marketing with major Korean partners.

Lemontree's regulatory perimeter (FSC-licensed electronic financial business), core infrastructure dependencies (KB Kookmin Card for processing, Hana Bank for trust deposits, Shinhan for brokerage, Korail/Rail Plus for transit), and content library create a defensible position in the Korean kids-fintech niche. The company is single-country (South Korea), employs 11–50 people, and operates from Seongnam (Bundang district). Strategic direction points toward becoming a regulated family finance super-app spanning card, education, investment, and tax services, with potential future expansion into adjacent youth lifestyle verticals via partnerships.

Name

Lemontree

Legal name

주식회사 레몬트리 (Lemontree Inc.)

Website

https://firfin.family

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Lemontree (레몬트리) operates Firfin (퍼핀), a South Korea–licensed family fintech platform providing a prepaid debit and transit card, parental allowance controls, and 2,000+ financial-education quizzes for children aged 7+, with recent extensions into parent-supervised investing and family wealth services.

Ownership category

akta.pro rank

Product category

Kids Fintech

NAICS

Credit Card Issuing (52221), Activities Related to Credit Intermediation (5223)

SIC

Personal Credit Institutions (6141)

akta.pro primary industry

Embedded Card Issuing & Card-as-a-Service (FSAGALAC)

akta.pro secondary industries

Prepaid Card Program Managers & Issuers (BIN Sponsors) (FSAMANAK), BaaS Platforms & Sponsor Bank Enablement (FSAGALAA), BNPL Consumer Apps & Wallets (Discovery, Management) (FSAGAIAG)

Keywords

• Prepaid debit cards
• Financial education platform
• Kids fintech services
• Allowance management app
• Family finance platform

Headquarters

HQ city

Seongnam

HQ country

South Korea

HQ region

Asia

Offices1 record

Markets served

GTM type

B2C

Offering type

Software

Cost components

Technology or R&D, Personnel, Marketing or Sales, Operations

Revenue model

1. Plus Membership Subscription: Premium subscription service offering unlimited access to exclusive educational content, bonus quizzes, book events, and special benefits. Billed on a monthly or annual cadence.
2. Transaction Interchange: Revenue share from payment transactions made with the Firfin card at KB Kookmin Card merchant terminals. A portion of the interchange fee from each card swipe and barcode payment flows to Lemontree.
3. Firfin Convenience Store (퍼핀머니샵): Online shop where children purchase gifticons (CU, GS25, McDonald's, Olive Young, etc.) using their Firfin money balance. Lemontree earns margin on gifticon sales.
4. Referral Program: Users invite friends and both receive 2,000 won in Firfin points. This drives user acquisition at a defined cost per acquired user.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels5 records

Core offering

Lemontree operates Firfin (퍼핀), a family financial platform providing prepaid debit and transit cards for children aged 7+, paired with a mobile app for allowance management and parental controls. The platform combines spending tools, real-time transaction monitoring, and 2,000+ gamified financial education quizzes, plus parent-supervised investment services through Shinhan Investment Securities.

Product overview

Lemontree operates Firfin (퍼핀), a unified family financial platform composed of multiple integrated products and modules. At its core is the Firfin App and the Firfin Card — a prepaid debit and transit card for children aged 7+ that enables allowance management, spending controls, barcode payments, and real-time parental monitoring. The platform is augmented by Firfin World, a gamified financial education content hub with 2,000+ economics quizzes; Firfin Investment, a parent-supervised stock investment feature backed by Shinhan Investment Securities; and the premium Firfin Membership (퍼핀 플러스) add-on offering exclusive content and promotions. A notable addition is 부자 패스 (Rich Pass), an integrated service for family wealth management including minor stock accounts, proxy trading, gift tax planning, and Hometax filing. The company also developed the 한국금융이해력평가 (KFQA), Korea's first recognized financial literacy assessment for children, offered in partnership with Maeil Business Newspaper. The platform is built on partnerships with KB国民Card (payment processing), Rail Plus (transit card), and Shinhan Investment Securities (brokerage), and is regulated as an official electronic financial service provider registered with the Financial Services Commission of Korea.

Differentiator

Problem solved

Functional benefit

Brands

• 퍼핀 (Firfin): Family financial platform for children's allowance management featuring prepaid cards with transportation functionality, financial education content, and investment services for children aged 7+.
• 부자 패스 (Rich Pass)

Products and services

• Firfin Platform (퍼핀) A family financial platform for Korean parents and children aged 7+ that combines a prepaid debit and transit card with a mobile app for allowance management, parental spending controls, and gamified financial education.
• Firfin Card (퍼핀카드) A prepaid debit card for children that doubles as a nationwide Rail Plus transit card, accepted at all KB Kookmin Card merchants. Issued via the Firfin app without requiring a bank account or branch visit, with free issuance, usage, and allowance transfer fees.
• Firfin Investment Service (퍼핀 투자 서비스) A parent-supervised stock investment service for children, allowing research, investment journal writing, and buy/sell orders through a Shinhan Investment Securities CMA account, with simulated US stock investing.
• Firfin Plus Membership (퍼핀 플러스) A paid subscription membership offering unlimited access to exclusive financial education content, premium quiz maps, curated book giveaways, and member benefits such as discounts on overseas English camps.
• Rich Pass (부자 패스) An integrated family financial service supporting minor stock account opening, parent-managed proxy stock trading, gift tax planning, and Hometax self-reporting for Korean families managing children's investments and wealth transfer.
• Korea Financial Literacy Assessment (KFQA, 한국금융이해력평가) A financial literacy assessment program for elementary school students, developed in partnership with Maeil Business Newspaper and sponsored by the Council for Youth Financial Education.

Quantifiable outcome

• 200,000+ users within one year of launch
• +2 more outcomes

Named customers2 records

Segments2 records

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration3 records

Feature5 records

Partnerships

Nine partnerships are on record, tiered core, minor and moderate.

• Shinhan Investment Securities (신한투자증권)coreStrategic or Co-development Partner · 27 March 2024Strategic MOU for children's investment education. Shinhan Investment Securities provides non-face-to-face securities account opening, financial education content, and stock investment services through the Firfin app. Children can open CMA accounts and learn investing with parent approval.
• Jangwon Education (장원교육)minorStrategic or Co-development Partner · 18 March 2024MOU to provide enhanced learning experiences combining Jangwon Education's professional character education with Firfin Plus membership. Joint '초등 시사 어휘력 강화 패키지' learning package offered to members.
• Korea Federation of Banks (은행연합회)moderateStrategic or Co-development Partner · 21 December 2023Bank-led social responsibility project to provide financial education for children and teenagers. Developed metaverse-based financial education quiz map 'Bank랑 놀자' within Firfin World, where children solve finance quizzes and earn rewards.
• Emart24 (이마트24)minorGTM or Marketing Partner · 7 December 2023Strategic MOU for joint marketing, co-developing collaborative products, and brand promotion using both companies' online and offline infrastructure. Emart24 targets future teen consumers through Firfin's young user base.
• Korea Railroad Corporation / Rail Plus (코레일/레일플러스)coreTechnology or IntegrationRail Plus transportation card function is embedded in the Firfin card. Children can use the card for public transit nationwide. Card charging and management is provided by Rail Plus.
• KB Kookmin Card (KB국민카드)coreTechnology or IntegrationPayment processing partner for Firfin card transactions. All card payments at KB Kookmin Card merchant terminals are processed through this partnership. Also provides the virtual account system for deposits.
• Hana Bank (하나은행)moderateTechnology or IntegrationVirtual account provider for user deposits. Changed from KB Kookmin Bank to Hana Bank in March 2026 for deposit accounts. Prepaid funds are held in Hana Bank trust accounts.
• Hope Bridge National Disaster Relief Association (희망브리지 전국재해구호협회)minorOthersCollaborated on disaster relief campaigns including the 2025 wildfire relief campaign where 843 families donated 6.8 million KRW using their Firfin allowance. Another flood relief campaign was conducted in summer 2025.
• MBC Union Camp (MBC 연합캠프)minorGTM or Marketing PartnerExclusive partnership offering Firfin members discounts on overseas English camps. Members receive 3% cashback (up to 200,000 KRW) on camp payments when registering through Firfin. Covers 14 camp programs across US, Canada, UK, Australia, New Zealand, Philippines, Singapore, and Jeju.

Scale indicators6 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• Greenlight Financial: US-based kids and teen debit card with parent controls and a robust financial education content layer. Closest global analog to Firfin's combined card-plus-education offering, serving a similar parent-child use case at materially larger scale.
• GoHenry: UK-originated prepaid card and financial education app for children aged 6–18 with parental controls and money-management learning. Directly comparable to Firfin in product design, age cohort, and core value proposition.
• Copper Banking: US teen-focused debit card and financial education platform. Comparable to Firfin's positioning as a first-card experience for minors combined with parent oversight and money lessons.
• Step: US teen banking and credit-building platform that combines a card account with financial education for under-18 users. Comparable to Firfin's card + education + investment-learning concept for a US teen audience.

Broad incumbents

• Toss: Korean super-app offering payments, banking, investing, and lifestyle services to tens of millions of Koreans. A domestic broad incumbent that could expand into minor-targeted financial services and compete with Lemontree's niche.
• Kakao Pay: Korean payments and financial services platform within the Kakao ecosystem. Most relevant domestic broad incumbent given Kakao Investment's existing stake in Lemontree — represents both distribution opportunity and competitive threat.
• Revolut (Under 18 / Revolut Junior): Global neobank that offers a Junior/Under-18 account with parent controls and allowance management within its broader adult super-app. Comparable feature set to Firfin's allowance + parent controls, though embedded inside a much larger incumbent platform.

Others

• Stash: US beginner-investing platform combining brokerage accounts with educational content. Comparable to Firfin's investment-education angle (including the $2,000 mock US stock portfolio feature), though targeted at adults.
• Acorns: US micro-investing app focused on beginner investors with educational content. Adjacent to Firfin's Firfin Investment feature, though Acorns serves adults and operates an investing-first rather than allowance-first model.

Regional players

• Mydoh: Royal Bank of Canada-owned smart money management and prepaid card app for Canadian kids and teens. Comparable to Firfin in parental controls, allowance management, and youth financial literacy positioning, but Canada-only.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks7 records

Key highlights7 records

Customer concentration

• Facebookfacebook.com/firfin.family

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds2 records

Investors9 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Lemontree