Fund lineup, minimum investment, automatic investing, NISA eligibility, point programs, credit-card investing, and screening tools.
For mutual funds, SBI, Rakuten, and Monex lead on very broad lineups, ¥100 minimums, recurring and card-based investing, and point programs — but a huge lineup can encourage needless fund proliferation, so a broad low-cost core still matters most.
For fund investors, SBI, Rakuten, and Monex stand out with very broad lineups, ¥100 minimums, and easy automation. You can set a monthly recurring purchase, and at supporting brokers fund it with a partner credit card to earn points. This combination makes steady, low-cost accumulation straightforward — the core of most beginners’ plans.
Check that your intended fund is available, NISA-eligible where you want it, and supported for recurring purchases. The big three cover the popular low-cost index funds, but exact availability and card integration differ.
A good broker provides screening and comparison tools — filtering by asset class, benchmark, cost, and NISA eligibility, and comparing funds side by side. These help you evaluate a fund on benchmark, expense ratio, tracking difference, and size. Use them to check that a fund is tracking its index sensibly and is cheap, not to rank funds by recent return.
The classic trap is selecting "last year’s best fund." Recent performance is an unreliable guide to future relative results; a top-ranked fund can lag next year. Let the tools inform a cost- and benchmark-based decision, not a performance chase.
A very large lineup has a downside: it tempts you to collect many overlapping thematic and regional funds, adding complexity and cost without real diversification. Owning ten funds that all hold the same US large caps is not more diversified than owning one broad global fund — it is just harder to manage.
Keep it simple. Decide your allocation, pick one broad low-cost fund as the core, and add anything else only as a deliberate, limited satellite. The best fund broker is the one that carries your chosen low-cost funds and automates them — the size of the total lineup is largely irrelevant to that goal.
Brokerage (NISA/iDeCo) · Rakuten Securities
A leading low-cost brokerage for NISA and index-fund investing, integrated with Rakuten points and Rakuten Bank.
Fees: Many domestic funds and trades are low- or no-commission — verify current fee schedule.
Brokerage (NISA/iDeCo) · SBI Securities
Japan’s largest online brokerage by accounts, with a very broad low-cost fund lineup and full NISA/iDeCo support.
Fees: Many trades and funds are low- or no-commission — verify current fee schedule.
Brokerage (NISA/iDeCo) · Monex
An established online brokerage often chosen for US-stock access and research tools, with NISA and iDeCo support.
Fees: Commissions vary by product; some funds/trades are low-cost — verify current schedule.
This is education, not a recommendation. Most beginners research low-cost, broadly diversified index funds — for example all-country (全世界株式) or S&P 500 trackers — rather than picking individual stocks, because low fees and diversification are within your control while returns are not. Understand that values fall as well as rise, match the risk to your time horizon, and never invest money you may need soon.