Calculus EIS Fund

The Calculus EIS Fund is the longest-running EIS fund, having been the first to launch in 1999. The fund has invested in 81 companies since the adoption of its current strategy in 2013/14, with total investment into those companies of £172 million.

The fund targets EIS-qualifying companies in the technology, healthcare and media sectors. It looks to invest at a later stage, ideally once the companies are more mature and could potentially have lower failure rates and shorter holding periods compared to start-ups. However, like all EIS investments, the Calculus EIS fund remains high risk.

Important: The information on this website is for experienced investors. It is not a personal recommendation to invest. If you’re unsure, please seek advice. Investments are for the long term. They are high risk and illiquid and can fall as well as rise in value: you could lose all the money you invest.

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  • Evergreen EIS fund 
  • Established in 1999
  • Aims to invest in mature, growth-focused, private businesses 
  • Focus on fast-growing sectors
  • Target return of 20% IRR with exits targeted after 3-5 years – not guaranteed 
  • Strong and experienced management team 
  • The fund targets a minimum portfolio of five companies with advance assurance
  • £30,000 minimum investment
  • Quarterly closes, with funds aiming to be fully deployed within 15- 18 months (not guaranteed)

The manager

Calculus Capital’s CEO and Chairman, John Glencross and Susan McDonald, made their first EIS investment in 1996. They founded Calculus Capital in 1999 and shortly after launched the UK’s first approved EIS fund. Calculus now manages £119 million in tax-efficient investments, split between this EIS fund, its VCT, and the media-focused Calculus Creative Content EIS Fund. 

The investment team is co-led by Alexander Crawford and Richard Moore who are responsible for sourcing and executing new deals, as well as advising portfolio companies. They are supported by a wider team of six, including Dominic Harris, who acts as Head of Portfolio Management and monitors companies post-investment. Both EIS funds and the VCT are managed by the same team due to the similarity of their investment mandates. 

Investment strategy

The Calculus EIS Fund is an evergreen offer that predominantly targets more mature private growth companies, rather than earlier-stage businesses. This is expected to improve the risk/return profile: failure rates for more established businesses tend to be lower, and the time to exit shorter. However, bear in mind that these are still young EIS-qualifying businesses, so like all EIS investments, they are by nature higher risk.

The investment team targets fast-growing sectors, currently with a bias towards technology, healthcare and media, where it believes the most compelling opportunities can be found. 

The investment team looks for companies with the following characteristics: 

  • Proven and competitive products and services
  • Primary constraint to growth is access to finance
  • Strong management teams
  • A clear market need
  • A clear route to exit 

A large proportion of investment opportunities come from Calculus’ investor base and management teams it has successfully backed in the past. Calculus Capital also benefits from its longstanding industry experience and its investment team’s personal networks of lawyers, advisers, and brokers.

On average, the investment team screens 700 deals a year, reviews around 150 companies and completes around 7 to 12 investments. When reviewing a deal, Calculus conducts its own comprehensive research then brings in external parties for in-depth financial, legal, and commercial due diligence.

Once investments are made, Calculus aims to mitigate risk by actively managing its portfolio companies. Calculus creates a 100-day plan with each company and works with management to formalise the company’s strategy for the next 3-5 years. Calculus usually takes a board seat and will monitor performance closely through monthly management information packs as well as providing ongoing support in areas such as executive coaching, strategy and financial planning. 

Target return

There is a target Internal Rate of Return (IRR) of 20%. This is a target and is not guaranteed.

Exit strategy

Calculus will actively look for potential exit options as soon as commercially possible after the end of the EIS three-year minimum holding period. In practice, it expects this to be four to five years from investment. Exits may be achieved through a variety of routes, including a trade sale, management buy-out, refinancing or IPO. Exits and timeframes are not guaranteed. 


In 2012/13 the fund moved from a strategy with a sector bias towards energy, industrials and oil & gas to a focus on technology, healthcare, and the creative industry. This strategy shift aligned with the significant restructuring of the Investment Team, most notably the hiring of the two current Co-Heads of Investment. 

Since then, the fund has invested in 81 businesses, with funds invested in those companies (pre- and post- the strategy change) totalling £172 million.

Each investor is expected to hold a portfolio of at least five companies with capital typically deployed over 15 to 18 months. 

Below are portfolio company examples from previous iterations of the fund. They are outlined to give a flavour of the types of companies you might expect but are unlikely to be part of a new investor's portfolio. 

Blue Wireless Technology – Calculus EISBlu Wireless Technology - largest investment

Blu Wireless is a firm leading the way in bringing ultra-fast millimetre wave (mmWave) wireless technology into homes and businesses through the rollout of Wi-Gig® and 5G networks. Blu Wireless has many of the world’s leading semiconductor and consumer electronics companies among its customers.

One new client is First Group, the leading UK transport operator. The deal will allow Blu Wireless Technology to introduce advanced wireless access across First Group services. It is anticipated this should increase data capacity available to train passengers by over 100x.

Calculus first invested in 2017 as part of a £6.6 million institutional and private investment round following the strategic investment round lead by ARM, the UK semiconductor and software design company earlier in 2017. Calculus provided follow-on funding in 2019 after the company demonstrated commercial success, winning a number of government and private contracts. In total, the EIS fund has invested £5 million into the company.

Hinterview – Calculus EIS.jpgHinterview – recent investment

Video recruitment software company Hinterview, was founded by Andy Simpson and Richard McLaren. They believed video would increasingly become the standard means of communication and remote working would gather pace. However, having experimented with existing “video interview” tools, they decided to build their own prototype and founded Hinterview in 2015.

Hinterview is designed for recruitment firms, hosting video interviews, improving client and candidate experience and allowing candidates to pre-record answers to interview questions. Ultimately that is expected to improve both new business wins and successful candidate placements. 

The platform is now available in 30 countries, with 58,000 minutes of video watched each month and £10 million in placements logged annually. The company has experienced strong growth in the last couple of years, helped by increased hybrid working following the pandemic.

Calculus first invested in the business as the lead in a £3 million Series A funding round in December 2021. That brings the total invested in the business to date to £6 million - following previous backing from crowdfunding platforms and the MMC-managed Greater London Investment Fund.

Cloudtrade – Calculus EIS.jpgCloudTrade – example of previous exit 

CloudTrade automates the production and processing of invoices, orders and freight and logistics documents. That helps to speed up order processing and reduces the chances of human error.

Since it was founded in 2010, the company has grown its client base to over 650 companies around the world, dealing with $20 billion worth of documents. CloudTrade’s patented technology is now used by a wide range of customers, from Aberdeen City Council to international giants like Vodafone and Qantas airlines.

Calculus first invested £2 million in the business in July 2018, through both its EIS fund and VCT. In October 2021, it was announced that the business was being acquired by Advanced, a leading provider of commercial software, resulting in a 4x return for the EIS fund. Past performance is not a guide to the future.

Every1Mobile Limited – example of previous failure 

As is to be expected, not all investments work out. Based in Brighton, Every1Mobile developed a communications platform for inclusion programmes across Africa. The company’s technology centred on the rapid uptake of mobile phone ownership in developing countries – creating new communication opportunities for populations that had historically been inaccessible. 

The company worked with clients to create campaigns based on three main themes: health, education, and the ability to earn a living. In one example, the business partnered with Unilever to reach shopkeepers in Africa’s largest slum, Kibera. 

Calculus first invested £2.2 million in the business in November 2017. However, the company struggled following the merger between the Department for International Development and the Foreign and Commonwealth Office, which reduced funding for international projects. As a result, the investment has been written down to nil.


The Calculus EIS fund has invested in 81 companies since adopting its current strategy in 2013/14 – with total investments into those companies of £172 million. The fund has achieved 48 full exits, of which 25 were profitable delivering an average multiple of 2.73x (October 2022), with proceeds worth £107.3 million. The remaining portfolio is valued at £98.8 million.

For funds more than five years old (2013/14 – 2015/16), on average, for every £100 invested, investors would have received £68.96 back in realised returns and have a portfolio balance remaining of £59.95.

The chart below shows the average performance of the total subscribed into the fund each tax year, based on valuations as at 5 October 2021, expressed on a £100 invested basis. Please note, individual investor portfolios’ performance will deviate from the average. Past performance is not a guide to the future. 

Performance per £100 invested per tax year

Source: Calculus Capital, as at 5 October 2021. Performance figures are supplied by Calculus and are net of all fees, based on Calculus Capital’s valuation methodology. Past performance is not a guide to future performance. In the above examples, initial tax relief of up to 30% could also apply. Remember tax rules can change and tax benefits depend on circumstances.

Risks – important

This, like all investments available through Wealth Club, is only for experienced investors happy to make their own investment decisions without advice. 

EIS investments are high-risk and should only form part of a balanced portfolio. As must be expected with early-stage investments, some or even all of the companies in the portfolio could fail: the fewer the companies included in the portfolio, the higher the risk of loss if things don’t go to plan. You should not invest money you cannot afford to lose.

There is no ready market for unlisted EIS shares: they are illiquid and hard to sell and value. There will need to be an “exit” for you to receive a realised return on your investment. Exits are likely to take considerably longer than the three-year minimum EIS holding period; equally, an exit within three years could impact tax relief.

To claim tax relief, you will need EIS3 certificates, normally issued once shares have been allotted. This can take several months: please check the deployment timescales carefully. Tax reliefs depend on the portfolio companies maintaining their EIS-qualifying status. Remember, tax rules can change and benefits depend on circumstances.

Before you invest, please carefully read the Risks and Commitments and the offer documents to ensure you fully understand the risks. 

Calculus Capital has an exclusive focus on EIS and VCT investments, both of which are subject to HMRC rules which can change frequently. This could leave the firm and its investee companies vulnerable if rules change unfavourably in future.


A summary of the main charges and savings is shown below. Some of these will be payable by the investor, whilst others by the investee companies. The investment may have additional charges and expenses: please see the provider documents, including the Key Information Document, for more details.

Investor charges
Full initial charge 4%
Wealth Club initial saving 1% (2% for existing investors)
Net initial charge through Wealth Club 3% (2% for existing investors)
Annual management charge 2%
Administration charge
Performance fee 20%
Investee company charges
Initial charge Variable
Annual charges Variable
All fees and charges are stated exclusive of VAT, which may be applicable in some cases. Any fees and charges payable by the investee companies or the underlying businesses do not directly come out of your investment. However, they will effectively reduce the returns generated by investee companies and therefore impact your investment.

More detail on the charges

Timing of the offer

The fund anticipates taking 15-18 months to fully deploy investor capital following the closing dates. However, it may take longer.

The next tranche deadline is expected to be 29 July 2022.

Our view

We view Calculus EIS, the longest-running of all EIS funds, as a sensibly managed offer. Its investment team has ample experience across both VCT and EIS investments and the two Calculus co-founders in particular have been active in the EIS space for more than two decades. 

The fund targets later-stage investments in an effort to minimise failures and reduce time to exit – although as with any EIS investment, it is still high risk. The fund will focus on high-growth sectors with a bias towards technology, healthcare and media investments. These broad sector exposures may provide additional diversification to the offer. 

Calculus’ well established market position has helped the team raise and deploy a sizeable amount of capital in the last 20 years. Many of those investments have been successfully exited, resulting in a stream of realised returns – past performance is not a guide to the future.

Wealth Club aims to make it easier for experienced investors to find information on – and apply for – tax-efficient investments. You should base your investment decision on the provider's documents and ensure you have read and fully understand them before investing. This review is a marketing communication. It is not advice or a personal or research recommendation to buy the investment mentioned. It does not satisfy legal requirements promoting investment research independence and is thus not subject to prohibitions on dealing ahead of its dissemination.

The details

Target return
20% IRR
Funds raised / sought
Minimum investment
29 Jul 2022
Last updated: 1 April 2022

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