The ISS will be deorbited in 2031, and no single replacement is planned

The International Space Station will end operations around 2031, when it will be deliberately brought down from orbit. There is no one spacecraft or station waiting to take its place. Instead, NASA and other space agencies are funding multiple private space stations and research platforms that will operate separately, each serving different purposes and customers.

This shift marks a major change: the ISS has been a government-owned, government-operated facility since 1998. Its successors will be owned and run by private companies, with government agencies buying time and research access rather than building and maintaining the hardware themselves. The transition will not be seamless — there will likely be gaps in continuous human presence in orbit, and some research capabilities may not transfer directly.

Key Takeaways

  • NASA is funding Axiom Space, Orbital Reef, and other private companies to build commercial space stations that will launch between 2026 and 2028.
  • No single station will replace the ISS; instead, multiple smaller platforms will operate at the same time, each with different research focus and customer base.
  • Private stations will be smaller than the ISS and designed to be profitable, meaning they will prioritize paying customers over pure research.
  • The ISS will be deorbited in a controlled descent over the Pacific Ocean, a process that will take several months and cost roughly $1 billion.
  • There may be a period of one to two years when no crewed space station exists in orbit, depending on when private stations become operational.

Axiom Space's commercial modules and timeline

Axiom Space is the furthest along in development. The company plans to attach its own modules to the ISS starting in 2026, then detach them after the ISS is deorbited to form an independent station. Axiom's first module will include research facilities, a cupola for Earth observation, and commercial office space that can be rented by companies and governments.

Axiom has contracts with NASA to provide crew transportation and research time. The company is also selling seats to private astronauts and has agreements with space agencies in the United Arab Emirates, Saudi Arabia, and other countries. By 2028, Axiom expects to have four modules in orbit, making it the largest commercial station in the early post-ISS era.

The company's business model depends on a mix of government contracts, private research, and tourism. This means some research that was done on the ISS for pure scientific value may not happen on Axiom unless a paying customer funds it.

Orbital Reef and other competing platforms

Orbital Reef is a joint venture between Blue Origin and Sierra Space, with funding from NASA. It is designed as a "mixed-use business park" in orbit, with separate modules for research, manufacturing, and tourism. Orbital Reef is scheduled to begin operations around 2027 or 2028, though the timeline has shifted several times.

Other companies in development include Starlab (a partnership between Nanoracks, Lockheed Martin, and Axiom) and XRISM, a smaller platform focused on specific research areas. China is also building its own space station, Tiangong, which is already crewed and will continue operating independently of Western stations.

Unlike the ISS, which was designed to be a single shared facility, these private stations will compete for customers and may not share research data or crew. This fragmentation means that some experiments that require a large, unified facility may become impossible to conduct.

The gap between ISS deorbiting and private station readiness

The timing is tight. NASA currently plans to deorbit the ISS in 2031, but Axiom and Orbital Reef are not may provide to be fully operational by then. If either station faces delays — which is common in spaceflight — there could be a gap of one to two years with no crewed space station in low Earth orbit.

During this gap, research that requires human presence would have to wait. Some experiments could be conducted on uncrewed platforms or on suborbital vehicles, but long-duration studies and real-time human observation would not be possible. Government space agencies are aware of this risk and have discussed extending the ISS's life, but the station's age and maintenance costs make that option increasingly expensive.

The gap also affects crew training and experience. Astronauts and cosmonauts have trained continuously on the ISS for over two decades. A break in crewed spaceflight operations would interrupt that pipeline and require retraining before the private stations are ready for full crews.

How the ISS will be brought down

The deorbiting process will not happen overnight. NASA and its partners plan a controlled descent that takes several months. Cargo spacecraft will dock with the ISS and fire their engines to lower the station's orbit gradually, allowing it to lose altitude in a predictable way.

The station will be aimed to break apart over the Pacific Ocean, far from populated areas. Larger pieces will burn up in the atmosphere; some debris will survive reentry and splash down in the ocean. The entire operation is expected to cost between $800 million and $1 billion and will require coordination between NASA, ESA (European Space Agency), Roscosmos (Russia), and JAXA (Japan).

This controlled deorbiting is safer and more expensive than straightforward letting the ISS fall uncontrolled. The alternative — abandoning the station and letting it decay naturally — would risk debris falling on populated land.

What research will and will not transfer to private stations

Some ISS research will move directly to private stations. Materials science, pharmaceutical development, and manufacturing experiments are attractive to commercial customers and will likely continue. Axiom and Orbital Reef are both marketing these capabilities to pharmaceutical companies and manufacturers.

Other research — particularly long-term studies with no when ready commercial value — may not find funding. Climate monitoring, fundamental physics experiments, and some biological research have been conducted on the ISS because it is a shared government facility. Private stations, which must be profitable, may not prioritize these areas unless a government agency pays for them.

Earth observation and remote sensing will likely continue, as these have both scientific and commercial value. Microgravity manufacturing is expected to grow on private stations, as companies see profit potential in producing materials that can only be made in zero gravity.

The role of government funding in private stations

NASA is not straightforward handing over space research to private companies. The agency is funding the development of private stations through contracts and agreements that may provide government access to research time and crew transportation. This is similar to how NASA now buys seats on SpaceX's Crew Dragon rather than operating its own spacecraft.

However, government funding is not unlimited. Private stations will have to balance government contracts with commercial revenue. If a paying customer offers more money than a government research project, the station operator may prioritize the paying customer.

International partners — ESA, JAXA, and others — are negotiating their own agreements with private station operators. This means that European and Japanese researchers may have access to different stations than American researchers, depending on which contracts their governments sign.

Frequently Asked Questions

Will there be a space station in orbit at all times after 2031?

Not necessarily. If private stations face delays, there could be a gap of one to two years with no crewed station in orbit. China's Tiangong station will continue operating, but Western space agencies and private companies may not have continuous access to it.

Can astronauts from different countries use the same private space station?

It depends on the station and the agreements in place. Axiom has contracts with multiple countries, so astronauts from different nations may work on the same platform. However, each private station will set its own policies, and some may restrict access based on government contracts or political relationships.

Will private space stations be as large as the ISS?

No. Early private stations like Axiom and Orbital Reef will be significantly smaller than the ISS. The ISS is about the size of a football field; private stations will be closer to the size of a large building. This means less research capacity and fewer crew members at a time.

What happens to the research being done on the ISS right now?

Some experiments will be completed before 2031. Others will be moved to private stations if they have commercial value or if a government agency funds them. Some research may straightforward end, as there will be no facility to continue it.

Why is NASA letting private companies run space stations instead of building a new government station?

Building and operating a large space station costs tens of billions of dollars over its lifetime. NASA decided it was more cost-effective to fund private companies to build stations and then buy access, rather than operate the hardware itself. This model has worked for cargo and crew transportation; the agency is explore the same approach to orbital facilities.