ASTS vs RKLB: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of October 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.

The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. ASTS and RKLB share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.

This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined ASTS and RKLB exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.

AST SpaceMobile (ASTS) is building a space-based cellular network designed to deliver broadband directly to ordinary, unmodified smartphones from satellites. Its goal is to let a standard phone connect to its large low-Earth-orbit satellites when it is out of range of terrestrial cell towers, providing coverage in remote areas, at sea, and during outages. The company has launched test and early commercial satellites (including its BlueWalker and BlueBird series) and has signed agreements and investments with major mobile network operators such as AT&T, Verizon, Vodafone, and Rakuten, as well as receiving strategic investment from Google. AST SpaceMobile is pre-profitability and only just generating revenue (~$115 million over the trailing twelve months, against a net loss of ~$619 million), spending heavily to manufacture and launch a constellation before it can generate meaningful subscriber or operator revenue. Headquartered in Midland, Texas, it is a speculative, high-risk, high-reward company whose value depends on successfully deploying its network and converting partnerships into paying traffic.

Full ASTS guide

Rocket Lab (RKLB) is a space company that builds rockets and spacecraft and provides end-to-end space services. Its established business is the Electron, a small orbital launch vehicle that is one of the most frequently flown small rockets in the world, carrying satellites for commercial, government, and defense customers. Rocket Lab is developing Neutron, a larger, partly reusable medium-lift rocket intended to compete for bigger payloads and constellation deployments, directly targeting the market SpaceX dominates.

Full RKLB guide

Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.

• ASTS drivers: Direct-to-device opportunity; Mobile-operator partnerships.
• RKLB drivers: Neutron medium-lift rocket; Space Systems growth.

A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: AST SpaceMobile is pre-profitability and early-revenue, with heavy ongoing cash burn to build and launch satellites: trailing free cash flow was about -$1.8 billion, against ~$2.29 billion of cash and ~$2.99 billion of debt as of mid-2026. For RKLB, rocket Lab is not yet consistently profitable and invests heavily in Neutron, so cash burn and capital needs are real until that program generates revenue: trailing free cash flow is about -$252 million and the company funded itself with about $1.53 billion of stock sales in the first half of 2026, diluting holders.

Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick ASTS if you believe its drivers more; RKLB if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the ASTS and RKLB guides.

ASTS. AST SpaceMobile cannot be valued on current earnings: at ~144x trailing sales and with consensus calling for a 2026 loss of ~$2.29 per share, the ~$16.6 billion market cap is a bet on the constellation and on analysts' ~$582 million revenue estimate for 2027. That bet has been repriced sharply in 2026 as launch timing slipped, with the stock down ~49% year to date as of October 16 and the analyst consensus at hold with a ~$74 mean target. Valuation remains highly sensitive to launch news, and the next checkpoint is the November 9 Q3 report (consensus EPS ~-$0.44 on ~$46 million of revenue).

RKLB. Rocket Lab trades as a high-growth space name valued on its Space Systems revenue, backlog and the future option value of Neutron rather than current profits; forward P/E is not meaningful with expected EPS near zero. Even after falling from a 52-week high of $151 to about $52, the stock sits near 43x trailing sales, so the October 2026 Neutron delay and the November 9 Q3 report (consensus revenue about $257 million) matter more to valuation than near-term earnings.

Headline figures (approximate, October 2026): ASTS shows market cap ~$16.6B (share price ~$42.52 on Oct 16, 2026), revenue (ttm) ~$115M; Q2 2026 ~$31.5M, net income (ttm) ~-$619M loss, EPS ~-$2.13, margins Gross ~39%, operating deeply negative (~-545%); RKLB shows revenue (ttm) ~$769 million, up ~62% year over year in Q2 2026, backlog ~$2.36 billion record (end Q2 2026), gross margin ~37% GAAP TTM; ~41.5% non-GAAP in Q2 2026, operating margin (ttm) ~-25%.

ASTS and RKLB are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined ASTS and RKLB exposure against your real portfolio. It is not an investment adviser.