NISA in a Bear Market: Should You Hold, Buy the Dip, or Wait?

For many Japanese retail investors who opened a new NISA account in 2024, this week marks a painful milestone: their first real bear market. The Nasdaq has entered bear market territory, the Nikkei is under significant pressure, and global equity markets are absorbing the shock of an escalating US-China tariff war. If your NISA balance is flashing red, here’s what you need to know.

Context: The NISA Generation

Japan’s revamped NISA system, launched in January 2024, dramatically expanded tax-free investment allowances — up to ¥3.6 million per year across “growth” and “tsumitate” (accumulation) accounts. The reforms sparked a wave of retail investment enthusiasm, with estimates suggesting millions of new investors opened accounts in the first year alone. Many of these investors allocated primarily to broad global equity funds or Japan-focused ETFs — assets that are now facing meaningful drawdowns.

What a Bear Market Actually Means for Long-Term NISA Holders

A bear market is defined as a decline of 20% or more from a recent peak. For an investor with a 20–30 year time horizon — the ideal profile for NISA — a bear market is, historically, an interruption rather than a terminal event.

Consider the historical record:

The 2018–2019 US-China trade war triggered a ~20% Nikkei decline. The market fully recovered within a year.
The COVID-19 crash of March 2020 saw the Nikkei drop ~30% in weeks. It recovered to new highs within months.
The 2008 Global Financial Crisis was severe and prolonged — but even that market eventually recovered and reached new highs over a multi-year horizon.

Long-term tsumitate (accumulation) investors actually benefit from volatility through the mechanism of yen-cost averaging: your fixed monthly contribution buys more units when prices are lower, reducing your average cost over time.

Hold, Buy the Dip, or Wait?

Here’s a practical framework depending on your situation:

If you’re a tsumitate (monthly accumulation) investor: Do nothing. Let the automatic contributions continue. Market downturns are when yen-cost averaging works hardest in your favor. Stopping contributions now would lock in losses and miss the recovery purchases.
If you have spare cash and a long time horizon (10+ years): Modest additional contributions to the growth NISA during a significant dip have historically been rewarding. Only invest money you genuinely won’t need for a decade.
If your time horizon is short (5 years or less): Reducing equity exposure toward capital-preservation assets may be prudent — though this applies regardless of market conditions.
If you’re tempted to sell everything: Ask yourself what has actually changed about the long-term business prospects of the companies in your index fund. Trade wars are cyclical; corporate earnings power over decades is not.

What Not to Do

The most common and costly mistake in bear markets is selling into panic and then waiting too long to re-enter. Markets tend to recover faster than sentiment does. The investors who missed the 10 best days of the 2009–2019 bull market saw their returns cut by more than half.

NISA’s tax-free advantage is most powerful over time. Selling now surrenders that advantage and creates a taxable event on future gains when you re-enter.

The Bottom Line

Bear markets are uncomfortable but not unusual. For NISA investors with long time horizons, the evidence-based answer is to stay the course, continue regular contributions, and resist the urge to time the market. The investors who built wealth through Japan’s prior market cycles did so through discipline, not perfect timing.