Once Christmas is over, I intend to start adding shares to my daughter’s Junior Self-Invested Personal Pension (SIPP). This is a pension for under 18s, where the money’s locked away until they reach pension access age.

Therefore, contributions I make today have many decades to compound, hopefully supporting a more comfortable retirement for her.

But what stocks to buy? Well, earlier this week Elon Musk announced he would give every US child in America a single SpaceX share next year. That might not sound much, but there were 72m children under 18 in the US in July 2025, according to official census data. So this equates to about $11bn at the current share price.

This got me wondering. Should I follow his lead and also put SpaceX in my daughter’s investment account?

The case for…

Now, the first thing I should declare is that I own SpaceX shares. So it helps that I already know a lot about the company and feel bullish on its long-term prospects.

These centre around SpaceX’s dual global leadership in rocket launches and global internet connectivity (Starlink). Indeed, these two businesses are interlinked as SpaceX uses its own rockets to put more and more Starlink satellites into orbit.

There are currently over 11,100 satellites operating — more than the nearest constellation rivals combined. Customers include remote farmers, airlines, cruise ships, oil platform operators, remote industrial sites, national security agencies and defence forces. Starlink also plans to aggressively roll out its direct-to-cell service to smartphone users.

This division’s currently at a $21bn annualised revenue run rate, with software-style profit margins, and the opportunity’s still early.

On top of this, SpaceX is renting out AI compute capacity to firms like Google and Anthropic. That’s in the here and now. But as launch costs continue to plummet, there’s the opportunity to put AI compute infrastructure into orbit.

There are other opportunities like space tourism and microgravity manufacturing that will open up for SpaceX over the next decade. So this is definitely a stock where it makes sense to buy and hold long term — making it a great fit for a Junior SIPP.

… the case against

Turning to reasons not to buy SpaceX, it already commands a gigantic market value. The current market-cap is $2trn. Therefore, the upside could be capped if the firm doesn’t realise its true growth potential. Indeed, it could turn out to be a dud.

Another risk is that Europe’s planning to limit spectrum access for non-US companies, according to the Financial Times. This could threaten Starlink’s growth across the continent.

Finally, the starting valuation’s quite high. Wall Street only expects SpaceX to turn profitable next year, so we’ve got a forward-looking price-to-earnings (P/E) ratio of 50.

That said, the P/E multiple does then start falling rapidly. So taking a longer-term view of the growth trajectory, I don’t think SpaceX is ridiculously overvalued today.

My decision

Weighing everything up, I’m leaning towards buying SpaceX shares for my daughter’s SIPP. But it obviously won’t be the only company (I plan to build out 15-25 investments over time).

As such, I do think SpaceX stock’s worth considering today. But who knows where it will be after Christmas?

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Ben McPoland owns shares in SpaceX.