Guidance

How to Apply for ESA BASS Call for Proposals

Updated 28 April 2026

This page outlines the formal application process for organisations seeking BASS funding in the Call for Proposals and Open Call funding opportunities only. It does not apply to the Enabling Studies, or Competitive Calls.

It only applies to entities located in the United Kingdom.

Find a list of all the currently open ACCESS BASS calls that the UK Space Agency is supporting.

We strongly advise applicants to review the application process in detail to ensure compliance with all requirements and to maximise the quality of their submission. The information provided here covers the submission procedure and stages of the assessment. ESA provide an overview of timelines on their website, although please be aware that these may vary depending on several factors.

Our aim is to ensure that all applicants have a clear understanding of our expectations at each stage and are well-prepared to move smoothly through each step of the process.

For further guidance or clarification, please refer to the supporting documentation or contact the UK Space Agency directly at space-applications@ukspaceagency.gov.uk.

Introduction

Under both the Call for Proposals and Open Call, you can submit both Proof of Concept (feasibility) Studies and Pilot Project (demonstration) activities. Proof of Concept Studies are limited to a maximum amount of funding which is shown on the call website, and a maximum duration of nine months. Pilot Projects do not have a maximum financial limit or duration. The UK Space Agency limits co-funding to 50% for both Proof of Concept and Pilot Project activities, despite what it says on the ESA website. For higher amounts of requested funding, and/or long duration proposals, we will require additional justification for your requests to support our assessments. We need to ensure we are balancing the level of risk we are considering against achieving the best value for the taxpayer.  

Calls for Proposals provide a thematic framework to help applicants consider what services could benefit from space-based data and assets. There are specific challenges set out as part of the call, and although you do not have to strictly address them, your proposal for a Proof of Concept Study or Pilot Project should fall within the broad theme of the call. Calls for Proposals follow the same applications process as the Open Call set out below. 

The Open Call is the most flexible in terms of the scope of the proposals accepted. You will need to demonstrate a solid business case opportunity, but you are not constrained by pre-determined thematic topics or sector needs. We do not accept solutions without a challenge, i.e. “build it and they will come” style proposals, so make sure you have a clear market opportunity to investigate for Proof of Concept, or to address for Pilot Projects.

The UK Ambassador platform 

Through the UK subscription to the ESA ACCESS BASS programme, our free to use Ambassadors are available to provide support, guidance, and critical friend feedback as you develop your Activity Pitch Questionnaire documentation. The Ambassadors will not write your proposal for you but can provide support and advice on BASS opportunities and support the preparation of your proposal. If BASS is not the right funding opportunity, they can provide information on other funding calls that might be more suitable. 

Find out more about the UK Ambassador Platform.

How to apply for funding 

The process below is sequential and requires you to start at step 1. You cannot skip steps or miss them out.  

Step 1: Activity Pitch Questionnaire (APQ) 

The Activity Pitch Questionnaire (APQ) is a concise and standardised pitch for applicants. This is the first step in the process for applicants, although we strongly recommend applicants consider working with the ESA Business Applications Ambassadors to ensure they are at a good standard before formally submitting.  

Companies submit their APQ’s via the ESA website and to the UK Space Agency’s space-applications@ukspaceagency.gov.uk in parallel for both organisations to have sight of the documentation for their own internal review processes. For Calls for Proposals the UK Space Agency cannot facilitate late submissions under any circumstances, so it is in your best interest to submit the APQ in good time in case there are any issues. 

To be eligible for consideration of UK Space Agency funding from the ESA ACCESS BASS programme, the idea described in your APQ must:

1. Use at least one space asset (such as Satellite Communications, Earth Observation, Satellite Navigation, Human Spaceflight technologies and other space assets). 

2. Develop commercially viable and sustainable space-based applications by linking user needs to corresponding solutions, which incorporate existing space assets and/or data, or requesting only limited technology adaptations. 

3. Demonstrate that the proposed solutions work in the proposed operational environments and are compatible with their operational practices (for Pilot Projects only).

Find out more about the Activity Pitch Questionnaire (APQ). 

For further guidance and support, you can directly contact our free to use Ambassadors. 

Step 2: Quality Assurance ​ 

The UK Space Agency will review your APQ alongside ESA. We aim to complete our assessment within 10 working days of acknowledgement of receipt of your APQ. ​ 

If the application meets ours and ESA’s standards, it will proceed to the next step of the process. ESA will respond to companies with a decision and provide feedback. 

Step 3: Develop an Outline Proposal 

If the APQ is approved by the UK Space Agency and ESA, companies must write an Outline Proposal (OP) and submit this to both ESA and the UK Space Agency. The OP builds on the business case in the APQ, providing additional detail on customer needs and engagement, the proposed solution and its alignment with those needs, competitor analysis, broader market opportunities, and technical information regarding service operations and the use of space assets. 

ESA Technical Officers support companies to develop an acceptable OP by ensuring there is sufficient information in the OP for the UK Space Agency to review.  

If approved, the UK Space Agency will invite successful companies to our BASS Assessment Panel and ask them to present their OP to a panel of experts. The UK Space Agency will inform ESA in advance before inviting companies. Companies who proceed to the BASS Panel without ESA sign off do so entirely at their own risk. 

Step 4: Assessment Panel 

The BASS Assessment Panel is a UK Space Agency-led process. The purpose of this step is for the UK Space Agency to gain further information about your proposal, ask clarifying questions, and to better inform our decision-making. The panel advises the UK Space Agency Space Data and Applications team and consists of a mix of independent, external subject matter experts and internal UK Space Agency staff. ESA BASS team members will often attend to observe the panel and provide additional context to help the panel reach a consensus. 

The UK Space Agency holds panels every two months, and provide companies with at least 10 working days with full details of what to expect on the day. We share the OPs with the panel experts two weeks prior to the BASS panel date giving them time to review and prepare for each panel session.  

For each proposal, the panel agree a collective recommendation on next steps and provide this to the UK Space Agency Space Data and Applications team. There are three potential outcomes from this; unconditional approval to proceed, requires further clarification, or not acceptable so do not proceed. If the panel require further clarifications, companies have four weeks to respond. 

If the panel are satisfied with the responses to the clarification questions or have given an unconditional approval, the UK Space Agency will inform the company, and ESA will formally invite them to submit a Full Proposal. 

If the proposal is not acceptable, we will provide feedback to the company within 10 working days of the assessment explaining the rationale.

Find out more about the subject matter experts who sit on the Assessment Panel

Step 5: Full Proposal 

Following a successful BASS Assessment Panel, companies must write a Full Proposal (FP), which is the last step in the documentation development process. The FP builds on the previous Outline Proposal and finalises all the details of the Business Case. It also forms the basis of any resulting contract with ESA as appropriate. 

The FP is a fully detailed business case clearly setting out the “what, why, when, where, how, and how much” of the proposal and contains the final costings, schedule, work packages descriptions, market analysis, use of space assets/data, and customer requirements that you intend to deliver as part of the project. 

There should be no ambiguities, uncertainties or unknowns in the FP, everything should be fully detailed, costed, resources, and explained. 

Once the FP is complete and has passed the ESA checks, the UK Space Agency Space Data and Applications team will assess it to ensure that any feedback from the Assessment panel in Step 4 has been addressed and that there are no significant deviations from the Outline Proposal in terms of time, cost, and performance. If we require clarifications during our assessment, we aim to contact the company within 10 working days of receipt. 

Step 6: Authorisation of Funding ​(AoF) 

After the UK Space Agency finishes reviewing your FP and you resolve any questions to the satisfaction of the National Delegate, we will issue an Authorisation of Funding that you need to include with your FP when you submit it to ESA. ESA require the AoF to accept your completed FP for assessment, as it specifically releases the funding requested, the ESA Price, for the proposed activities. Without a valid AoF, ESA will not review your proposal. 

AoFs are valid for 6 months from the date of issue. This is to try to ensure that the next steps happen in a reasonable timescale, and if there are delays beyond six months, we can examine the causes and check the business case is still valid before considering an extension. 

Step 7: Submit completed proposal to ESA​ 

Once an AoF is issued the completed documentation set, including, but not limited to, the full proposal, any PSS forms, any letters of support from potential customers, any annexes that have been added, needs to be submitted to ESA via their official web portal. Your ESA Technical Officer will provide you with the details on how to do this. 

Step 8: ESA processes ​ 

Once you submit your completed Full Proposal and AoF to ESA, the UK Space Agency Space Data and Applications team are no longer involved, and you should direct all queries to your ESA Technical Officer. 

An independent ESA team check the submitted Full Proposal to ensure it contains everything necessary ahead of conducting an assessment and evaluation. Having completed final checks, ESA and contract team meet with applicants to negotiate the final contract for delivering the proposal. Upon successful completion of the negotiation meeting ESA and the applicant sign the contract shortly after.

Find out more about ESA’s process.