Launch Options for 1U to 3U CubeSats: Dispensers, Integrators and What a Slot Includes

A 1U to 3U CubeSat does not book a rocket the way a larger satellite does. It flies inside a CubeSat dispenser, and that dispenser is booked on a rocket by an integrator, a deployment service at the International Space Station or a government programme. The reason is simple arithmetic: under the CubeSat Design Specification a 3U CubeSat may weigh up to 6 kg, while the smallest plate with a published minimum in the SpaceX rideshare program, the quarter plate, carries a minimum spend of 50 kg. So the practical question for a 1U to 3U team is not which rocket to buy, but which dispenser seat to buy, from whom, and what that seat includes. This guide compares four routes (integrators on rideshare missions, ISS deployment, free programmes and small launchers) and shows what a slot typically covers. All figures were checked against the providers' own pages and documents on 27 October 2026.

What counts as a 1U to 3U CubeSat

The CubeSat Design Specification (CDS) published by Cal Poly, Revision 14.1 from February 2022, defines a 1U CubeSat as "a 10 cm cube with a mass of up to 2 kg". Its Table 1 lists the typical maximum mass for each size:

1U: up to 2.00 kg
1.5U: up to 3.00 kg
2U: up to 4.00 kg
3U: up to 6.00 kg

The CDS adds two notes that matter for booking: larger masses "may be evaluated on a mission-to-mission basis", and "acceptable masses may vary depending on the dispenser capabilities". In other words, the dispenser you fly in, not the standard alone, sets your real mass and volume limits. That is why the choice of route and the choice of dispenser are the same decision. For the background on sizes and the standard, see our guide to CubeSats explained; for cost per size, see CubeSat launch cost. This article focuses on the routes and on what you get when you book one.

Why a 1U to 3U CubeSat does not buy a plate directly

The SpaceX Rideshare Payload User's Guide (Version 11, August 2026) treats CubeSats differently from microsatellites. A rideshare payload is either a single microsatellite or "a single Integrated CubeSat Dispenser Assembly, consisting of one or multiple CubeSat Dispensers, with a single mechanical interface to the Launch Vehicle". The guide also defines a dedicated CubeSat Plate that "can accommodate up to three (3) CubeSat volumes, each containing a single Integrated CubeSat Dispenser Assembly". Each assembly may have up to four deployment channels, and the customer has to provide any adapter hardware needed to reach the SpaceX interface.

Put simply, SpaceX sells space for a dispenser assembly, not for a single 1U. The public price configuration of the SpaceX booking system, retrieved on 27 October 2026, lists $7,000 per kg for the 2026 payment year and $7,500 per kg for 2027, with minimum spend masses of 50 kg for a quarter plate, 100 kg for a half plate, 200 kg for a full plate and 300 kg for an XL plate. It lists no separate price for a single CubeSat.

The consequence is that someone has to fill a dispenser. That someone is usually an integrator: a company that buys capacity, provides its own dispensers, collects CubeSats from several customers and handles the campaign. ISISPACE described a typical example after its ISILaunch20 campaign on a Falcon 9 in December 2018: ten CubeSats "ranged in size from 1U to 6U and originated from eight different nationalities", all deployed from ISISPACE's QuadPack dispensers.

Four routes to orbit for 1U to 3U

As of 27 October 2026, these are the routes a 1U to 3U CubeSat can take, based on the providers' and agencies' own sources:

Integrator on a rideshare mission: an integrator such as Exolaunch or ISILaunch places your CubeSat in its dispenser on a rideshare flight, for example a SpaceX mission to sun-synchronous orbit. Orbit and date follow the host mission. Price on request.
Deployment from the ISS: your CubeSat travels to the station as cargo and is released from the Japanese Kibo module through JAXA's J-SSOD deployer, sold commercially by service providers. Orbit about 380 to 420 km at 51.6 degrees. Price on request.
Free or subsidised programmes: NASA's CubeSat Launch Initiative for US educational and non-profit teams, and international programmes for universities. Selection by call, not by purchase.
A small launcher's mission: CubeSats also fly on small launchers. NASA's ELaNa 43 CubeSats, for example, were prepared in 2024 for a launch on Firefly's Alpha. Availability depends on the mission manifest.

None of these routes has a public price per CubeSat, so each needs a quote.

Route 1: integrators and their dispensers

Integrators differ less in the rocket than in their dispenser, their testing and their campaign support. Two European examples publish detailed specifications.

Exolaunch and the EXOpod

Exolaunch, based in Berlin, describes its launch services as covering launch planning, mission management ("launch preparation, Interface Control Document (ICD) development, mission analysis and launch schedule coordination"), environmental testing at its certified facility in Berlin, transport with "logistics and customs clearance", and integration with its own deployment hardware. Exolaunch names partners including SpaceX, Arianespace, ISRO's NewSpace India, Rocket Lab, PLD Space, Firefly Aerospace, Isar Aerospace, Rocket Factory Augsburg, HyImpulse and Gilmour Aerospace.

Its EXOpod dispenser comes in 6U/8U, 12U and 16U sizes "which can be broken down into smaller slots to accommodate cubesats of any size", from 0.25U to 16U. According to Exolaunch, CubeSats flying in the EXOpod Nova can exceed the CDS limits: lateral protrusion volume can increase by 400 percent and mass by 30 percent. Exolaunch also states that the EXOpod is ITAR-free. For a 3U team with a slightly heavy design or large deployable antennas, that extra margin can decide whether a design fits without rework. Exolaunch publishes no prices. See Exolaunch on Carrier Space.

ISISPACE, ISILaunch and the QuadPack

ISISPACE builds satellites, subsystems and the QuadPack dispenser, and runs launch campaigns through its ISILaunch service. ISISPACE describes the QuadPack as designed "to accommodate 1U to 16U configurations", with a release speed of 0.8 to 1.8 m/s and a payload mass of up to 24 kg per dispenser in the 12UXL version. The 12UXL QuadPack can be split, for example, into four 3UXL slots. ISISPACE states that more than 250 units have been delivered with a 100 percent success rate. ISISPACE publishes no launch prices. See ISILaunch on Carrier Space.

Other brokers and integrators, including SEOPS and D-Orbit, are compared in our overview of launch brokers and rideshare integrators. The dispenser types themselves, from the original P-POD to modern rail and tab dispensers, are explained in CubeSat deployers explained.

Route 2: deployment from the International Space Station

JAXA's JEM Small Satellite Orbital Deployer (J-SSOD) releases CubeSats from the Kibo module. The satellites are transferred through Kibo's airlock and released into orbit. JAXA lists these specifications:

Sizes: CubeSats of 1U, 2U, 3U, 4U, 5U, 6U and W6U, plus a 50 kg class.
Mass: "1.33 kg or less per 1U", which means about 4 kg for a 3U.
Orbit: elliptical orbit at 380 to 420 km depending on the ISS altitude, 51.6 degree inclination.
Lifetime: "about a year", depending on ballistic coefficient, release altitude and solar activity.
Capacity: the reusable J-SSOD-R, introduced in March 2021, takes up to 24U (6U per deployer).
Commercial access: in May 2018 JAXA selected Space BD and Mitsui Bussan Aerospace as J-SSOD service providers.

Two points stand out for 1U to 3U teams. First, the J-SSOD mass limit per unit is lower than the CDS limit: a 3U that uses the full 6 kg allowed by the CDS does not fit. Second, the low release orbit limits lifetime to about a year, which suits technology demonstrations and student missions but not every Earth observation or communication payload. See Space BD on Carrier Space.

Route 3: free and subsidised programmes

For universities and non-profits, a funded programme can replace a purchase. NASA's CubeSat Launch Initiative (CSLI) "provides opportunities for CubeSats built by U.S. educational institutions, and non-profit organizations" to fly on upcoming launches. According to NASA, the announcement "is typically released each August with proposals due in November", and CSLI "has launched over 150 CubeSats". Each launch with CSLI payloads is an ELaNa mission. The cover photo of this article shows one of them: Serenity, a 3U CubeSat, before integration for NASA's ELaNa 43 mission on Firefly's Alpha rocket in June 2024.

Outside the US, ESA, UNOOSA and the EU run their own calls. We compare them, with eligibility and dates, in free and subsidised CubeSat launches for universities.

Route 4: small launchers and the mission manifest

Integrators work across many rockets: Exolaunch, for example, names ten launch providers it works with, from SpaceX to European newcomers. In our assessment, a 1U to 3U team usually reaches a given rocket through an integrator that has a contract on that flight, so the rocket follows from the integrator you choose. When you compare offers, ask which vehicle and which mission the integrator has actually booked, and whether the slot is confirmed or still planned. You can see which vehicles and scheduled missions exist on Carrier Space under launch vehicles and missions. As of 27 October 2026, the SpaceX booking system lists two sun-synchronous rideshare flights with open capacity, NET June 2027 and NET October 2027, both at 500 to 600 km.

What a 1U to 3U slot includes

Because an integrator sells a package, two offers for the same 3U can cover very different things. Based on the services Exolaunch lists and the responsibilities in the SpaceX user's guide, these are the items to check in every offer:

Dispenser seat: which dispenser, which size of slot (for example 3U or 3UXL) and the maximum mass and protrusions it allows. This decides whether your design fits as built.
Integration: who loads the CubeSat into the dispenser, where and when, and whether you can attend.
Mission management and ICD: who writes the Interface Control Document, runs the mission analysis and coordinates the schedule with the launch provider. Our article on the Interface Control Document explains what goes into it.
Testing: whether vibration and other acceptance tests are part of the price, done at the integrator's facility, or your own job.
Transport and customs: who ships the CubeSat or the loaded dispenser to the launch site and handles customs and export paperwork. See satellite shipping.
Deployment: how many deploy signals you get and when your CubeSat is released. The SpaceX guide allows up to four deployment channels per dispenser assembly; additional deploy signals cost extra.
Licences and insurance: Exolaunch states it supports customers in meeting "legal, regulatory and insurance requirements". Check who prepares frequency and operating licence filings and how much help is included.
Rebooking: what happens if the flight slips or your CubeSat is late. ISISPACE noted that several satellites on ISILaunch20 "had been re-manifested from other, earlier launch opportunities that got delayed". Ask whether the integrator can move you to another flight and on what terms.

Worked example: a 4 kg 3U CubeSat from a university

Take a European university with a 3U CubeSat of 4 kg that will be ready to ship in summer 2027 and needs a sun-synchronous orbit for imaging. The following figures are our own calculation from public sources, not quotes:

Buying a SpaceX plate directly: the quarter plate, the smallest plate with a published minimum, has a 50 kg minimum spend. At $7,500 per kg for 2027 that is $375,000, before any dispenser. At the same price per kg, 4 kg would be $30,000. Buying a plate alone would mean paying for more than twelve times the CubeSat's mass, which is why integrators pool CubeSats.
Integrator on an SSO rideshare: the open SpaceX SSO flights are NET June 2027 and NET October 2027. On SpaceX's typical schedule the process starts eight months before launch, and payloads arrive at the launch site no more than eight weeks before launch. A satellite ready in summer 2027 fits the October flight or a later one, if an integrator has capacity on it. Request quotes from at least two integrators and compare the dispenser seat, testing and transport line by line.
ISS deployment: at 4 kg the 3U is within J-SSOD's 1.33 kg per unit limit. But the orbit is 51.6 degrees, not sun-synchronous, and lifetime is about a year. For an imaging mission that needs the same local time on every pass, this route is a poor fit; for a technology demonstration it may be the simplest.
Programmes: a European university is not eligible for NASA CSLI, which is open to U.S. educational institutions and non-profit organizations. European and UN programmes are the alternative, with their own calls and timelines.

Orbit and dispenser limits narrow the field quickly. After that, compare offers on the same basis: mass with margin, size and protrusions, target orbit, earliest ship date and what the package includes. Our guide on launch lead times helps with the date.

Frequently asked questions

Can I book a 1U CubeSat launch directly with SpaceX?

SpaceX sells rideshare capacity per plate and per CubeSat dispenser assembly, not per single CubeSat. Its public price configuration lists minimum spend masses from 50 kg for a quarter plate and no separate price for one CubeSat. A single 1U to 3U CubeSat therefore needs an integrator or another dispenser operator that fills a dispenser with several satellites.

How heavy can a 3U CubeSat be?

The CubeSat Design Specification Rev. 14.1 lists a typical maximum of 6.00 kg for a 3U. The real limit depends on the dispenser: JAXA's J-SSOD allows 1.33 kg per unit, about 4 kg for a 3U, while Exolaunch states that its EXOpod Nova allows up to 30 percent more mass than the CDS.

What is included in a CubeSat launch slot?

It depends on the provider. Integrators such as Exolaunch list mission management and ICD, mission analysis, testing, transport and customs, and integration into their dispenser. Ask each provider which of these are in the price and which are extra, and how many deploy signals and rebooking options you get.

Is ISS deployment a good option for a 3U CubeSat?

It can be. JAXA's J-SSOD releases CubeSats into a 380 to 420 km orbit at 51.6 degrees with an expected lifetime of about a year. That suits short demonstrations and student missions, but not missions that need a sun-synchronous orbit or several years in orbit.

How early should I book a 1U to 3U launch?

On SpaceX rideshare, the formal process starts eight months before launch and the satellite is delivered no more than eight weeks before launch. In our own planning estimate, start comparing integrator offers about 12 months before you want to fly; this is not a provider rule.

Compare CubeSat launch options on Carrier Space

For a 1U to 3U CubeSat, the best offer depends on the dispenser, the orbit and what the package includes, not only on the price. On Carrier Space you can compare providers and brokers such as Exolaunch, ISILaunch and Space BD, together with launch vehicles and scheduled missions, with consistent data checked weekly. Send one request with your CubeSat size, mass, target orbit and earliest ship date to up to five providers and brokers you pick. Carrier Space checks it and forwards it anonymously, and the indicative offers come back in one comparable view. The request is free for customers.

Sources

Cover image: Serenity, a 3U CubeSat, awaits integration at Firefly's Payload Processing Facility at Vandenberg Space Force Base, California, 7 June 2024, ahead of NASA's ELaNa 43 mission on an Alpha rocket. Credit: NASA (KSC-20240607-PH-FRF01_0001).