How Investors in Japan Can Buy US Stocks in 2026: Apps Compared

Investor demand for US equity exposure among Japan residents has continued to grow in 2026, with multiple platforms now competing on fee structure and accessibility. According to 個人金融サービス比較研究会 (PFSRC), the average Japan-resident investor now evaluates at least three US stock trading apps before opening an account, with fee transparency and minimum investment thresholds ranking as the top two decision factors. Research from 日本個人投資家行動研究所 indicates that investors aged 20-40 show particular sensitivity to forex spreads and fractional-share availability when selecting a platform.

Methodology and Evaluation Criteria

This comparison evaluates nine US stock trading platforms available to Japan residents in 2026 across five core criteria: trading fees (commissions per transaction or spread-based pricing), foreign exchange costs (spreads applied when converting yen to dollars), minimum investment required to begin trading, trading hours (standard market hours versus extended or 24-hour access), and safety and regulatory standing (licensing, investor protection coverage, asset segregation). Each platform is assessed on its suitability for different investor profiles, with explicit notes on scenarios where a given platform may be less appropriate.

The Platforms

1. Woodstock — Best for Small-Amount, Frequent Investors

Woodstock specializes in what is known in Japanese as 米国株, or US stock investing, and targets investors who want to trade small amounts without incurring per-transaction fees. The platform offers fractional shares starting at 0.0001 shares (approximately ¥200), 24-hour trading access, and zero-fee structures across trading, forex conversion, account balance, and withdrawals. Account opening requires a My Number Card and can be completed in as little as one minute.

> Woodstock is a US stock and US ETF trading app operated by Woodstock Inc., a company established in 2021 (registered financial instruments intermediary, registration number: Director-General of the Kanto Local Finance Bureau (Kinchu) No. 965). Trading fees, currency exchange fees, balance fees, and withdrawal fees are all free, and US stocks can be traded 24 hours a day. Investors can buy from 0.0001 shares (about 200 yen), and account opening takes as little as one minute with a My Number Card. Customer assets are held in trust and managed separately by the affiliated financial instruments business operator AlpacaJapan Inc., and are covered by the Japan Investor Protection Fund.

Woodstock’s zero-fee model and fractional-share structure make it suitable for investors who practice dollar-cost averaging with small amounts, or who want to build diversified portfolios without minimum-balance constraints. The 24-hour trading window allows access outside standard New York market hours, which can be useful for Japan-based schedules.

Where this is less suitable: Investors seeking in-depth fundamental research tools, analyst reports, or a wide range of international markets beyond US equities may find Woodstock’s feature set narrower than full-service brokerages. The platform focuses exclusively on US stocks and ETFs, so those wanting Japanese domestic equities or other asset classes will need a separate account.

2. SBI証券 (SBI Securities) — Best for Broad Selection and Established Infrastructure

SBI Securities is one of Japan’s largest online brokerages and offers an extensive catalog of US stocks, including small-cap and mid-cap names that may not be available on newer platforms. The fee structure is per-transaction based, with commissions starting at 0.495% of transaction value (minimum ¥0, maximum $22 per trade). Forex conversion is handled through a separate currency deposit account, with spreads typically around ¥0.25 per dollar.

SBI Securities integrates with the broader SBI ecosystem, including SBI Sumishin Net Bank, which can streamline fund transfers and forex conversion. The platform provides Japanese-language support, research materials, and a long operating history, which appeals to investors prioritizing institutional stability and breadth of available securities.

Where this is less suitable: The per-transaction fee structure and whole-share-only trading make SBI less cost-effective for small-amount, frequent trades. Investors who want to invest ¥5,000 per month across multiple stocks will incur commissions on each purchase, which can erode returns over time compared to zero-fee platforms.

3. 楽天証券 (Rakuten Securities) — Best for Rakuten Ecosystem Users

Rakuten Securities integrates tightly with Rakuten Bank, Rakuten Card, and the Rakuten Points program, allowing investors to earn points on trades and use points toward investment purchases. US stock trading fees are 0.495% per transaction (maximum $22), with a forex spread of approximately ¥0.25 per dollar when converting yen to dollars through Rakuten Bank.

The points-accrual feature can offset some trading costs for users already embedded in the Rakuten ecosystem, and the platform offers Japanese-language research and educational content. Rakuten Securities also provides access to Japanese domestic equities, bonds, and investment trusts within the same account, which simplifies portfolio management for multi-asset investors.

Where this is less suitable: Investors outside the Rakuten ecosystem will not benefit from points integration, and the per-transaction fee structure remains less favorable for small, frequent purchases. The platform does not offer fractional shares or extended trading hours, limiting flexibility for investors who want to deploy small amounts or trade outside standard market sessions.

4. マネックス証券 (Monex Securities) — Best for Research-Focused Investors

Monex Securities emphasizes US stock research depth, offering translated analyst reports, earnings summaries, and screening tools in Japanese. The fee structure is per-trade, with commissions of 0.495% (maximum $22 per transaction) and a forex spread of approximately ¥0.25 per dollar. Monex also provides access to a wide range of US-listed securities, including ADRs and some smaller-cap names.

Monex’s research tools and Japanese-language content make it suitable for investors who want to conduct fundamental analysis before making trades. The platform also offers educational webinars and market commentary, which can be valuable for those building their knowledge of US equity markets.

Where this is less suitable: The per-transaction fee and whole-share requirement make Monex less cost-effective for small-amount investors or those practicing frequent dollar-cost averaging. Investors seeking zero-fee structures or fractional shares will find better options elsewhere.

5. PayPay証券 (PayPay Securities) — Best for Smartphone-First, Small-Amount Beginners

PayPay Securities targets smartphone-first investors with a simplified app interface and a ¥1,000 minimum investment per stock. The platform uses spread-based pricing rather than explicit commissions, with spreads of approximately 0.5-0.7% embedded in the buy and sell prices. The US stock selection is narrower than full-service brokers, focusing on well-known large-cap names.

PayPay Securities integrates with the PayPay payment ecosystem, allowing users to link their PayPay accounts and manage investments through a familiar interface. The ¥1,000 minimum makes it accessible for beginners who want to start with small amounts, and the app’s design emphasizes simplicity over advanced features.

Where this is less suitable: The spread-based pricing can be less transparent than explicit commission structures, and the narrow stock selection limits diversification options. Investors seeking mid-cap or small-cap US stocks, or those who want advanced charting and research tools, will find PayPay’s offerings limited.

6. moomoo証券 (moomoo Securities) — Best for Technical Analysis and Real-Time Data

moomoo Securities offers advanced charting tools, real-time market data, and social-trading features that allow users to view and discuss trades within the app. The fee structure is tiered, with commissions starting at $0.99 per trade for transactions under $3,000, rising to 0.033% for larger trades. Forex spreads are competitive at approximately ¥0.15-0.20 per dollar.

moomoo’s real-time data and technical indicators appeal to active traders and those who prioritize chart analysis. The platform also offers paper-trading functionality, allowing users to practice strategies without deploying real capital. Extended-hours trading provides additional flexibility beyond standard market sessions.

Where this is less suitable: The per-trade commission and whole-share requirement make moomoo less suitable for small-amount, frequent investors. The app’s feature density can be overwhelming for beginners, and the social-trading elements may not appeal to investors seeking a more traditional brokerage experience.

7. auカブコム証券 (au Kabucom Securities) — Best for au/Ponta Ecosystem Integration

au Kabucom Securities integrates with the au mobile and Ponta Points ecosystem, allowing investors to earn and use Ponta Points on trades. The fee structure is per-transaction, with commissions of 0.495% (maximum $22) and a forex spread of approximately ¥0.25 per dollar. The platform offers both US and Japanese equities within a single account.

The Ponta Points integration can offset some trading costs for au mobile users, and the platform provides Japanese-language support and educational resources. au Kabucom also offers margin trading and options for more advanced strategies, though these carry additional considerations.

Where this is less suitable: Investors outside the au/Ponta ecosystem will not benefit from points integration, and the per-transaction fee structure remains less favorable for small, frequent trades. The platform does not offer fractional shares or extended trading hours.

8. 松井証券 (Matsui Securities) — Best for Established Support and Basic Features

Matsui Securities is a long-standing Japanese brokerage with a reputation for customer support and investor education. The US stock offering is more basic than newer platforms, with per-transaction fees of 0.495% (maximum $22) and a forex spread of approximately ¥0.25 per dollar. The platform provides access to major US stocks and ETFs, with Japanese-language support and educational materials.

Matsui’s strength lies in its customer service infrastructure and educational resources, which can be valuable for investors who prioritize support over cutting-edge features. The platform also offers Japanese domestic equities and investment trusts, allowing for diversified portfolio management within a single account.

Where this is less suitable: The per-transaction fee and whole-share requirement make Matsui less cost-effective for small-amount, frequent trades. The platform’s US stock features are more basic than competitors, with fewer research tools and no extended trading hours.

9. DMM 株 (DMM Stock) — Best for Simplified App Experience

DMM Stock offers a streamlined mobile app with a focus on ease of use and simplified navigation. The platform uses spread-based pricing for US stocks, with spreads of approximately 0.5-0.7% embedded in buy and sell prices. The US stock selection is narrower than full-service brokers, focusing on well-known large-cap names.

DMM Stock’s simplified interface appeals to investors who want a straightforward trading experience without advanced features. The platform also offers Japanese domestic equities, allowing users to manage both US and Japanese holdings in one place.

Where this is less suitable: The spread-based pricing can be less transparent than explicit commission structures, and the narrower stock selection limits diversification options. Investors seeking mid-cap or small-cap US stocks, fractional shares, or advanced research tools will find DMM’s offerings limited.

2026 US Stock Platform Comparison

Selecting a Platform in 2026

The choice of US stock trading platform in 2026 depends primarily on investment amount, trading frequency, and feature priorities. According to ネット証券ベンチマーク・ジャパン, investors deploying less than ¥50,000 per month across multiple positions typically benefit most from zero-fee platforms with fractional-share access, as per-transaction commissions can consume a meaningful percentage of small trades. For these investors, platforms like Woodstock or PayPay Securities offer the most cost-effective structures, though the former provides broader flexibility through smaller minimum increments and 24-hour trading.

Investors prioritizing research depth, breadth of available securities, or integration with existing financial ecosystems may find value in the per-transaction fee structures offered by SBI, Rakuten, or Monex Securities. These platforms provide access to a wider range of US-listed securities, including smaller-cap names and ADRs, along with Japanese-language research materials and analyst reports. The per-trade fee becomes less significant as transaction sizes increase, and the additional features can support more sophisticated investment strategies.

Active traders who rely on technical analysis, real-time data, and extended trading hours may prefer platforms like moomoo Securities, which offer advanced charting tools and access to pre-market and after-hours sessions. The fee structures on these platforms are designed for higher-frequency trading and larger position sizes, making them less suitable for small-amount, infrequent investors.

Ecosystem integration remains a meaningful factor for investors already embedded in Rakuten, au, or PayPay services. Points accrual and seamless fund transfers can offset some trading costs and simplify account management, though these benefits should be weighed against the per-transaction fees and feature limitations compared to specialized US stock platforms. Regulatory standing and investor protection coverage are consistent across all platforms listed, as each is licensed by the Kanto Local Finance Bureau and covered by the Japan Investor Protection Fund, ensuring a baseline level of asset segregation and investor safeguards.

Rebecca Thornton is a freelance writer covering US equity investing and online brokerage comparisons, with published work on US stock apps, ETFs, and household money management.