Calculus EIS Fund

The Calculus EIS fund has the longest track record of any EIS fund. It was the first to launch in 1999 and is still going strong. This latest offer seeks to raise £20 million and focuses on established unquoted businesses with growth potential. 

Important: The information on this website is for experienced investors. It is not advice nor a research or 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, so you could get back less than you invest.

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  • Award-winning, evergreen EIS fund 
  • Established in 1999
  • Aims to invest in growth-focused, mature unlisted businesses 
  • Wide range of sectors
  • Strong and experienced management team 
  • The fund targets a minimum portfolio of 6 companies with advance assurance
  • £30,000 minimum investment
  • Quarterly closes, with funds aiming to be fully deployed within 18 months (not guaranteed)

The manager

Calculus Capital managing partners John Glencross and Susan McDonald made their first EIS investment in 1996. They launched the UK’s first approved EIS fund in 1999; it raised £1 million. 

Calculus has won the EIS Association Awards ‘Best EIS Fund Manager’ five times as well as Best EIS Fund Manager at the 2018 Growth Investor Awards: note past performance is not a guide to the future.

Calculus also manages a smaller amount in its VCT and media-focused UK Creative Content EIS fund.

Watch an exclusive video interview with Calculus CEO John Glencross:

Investment strategy

The Calculus EIS fund is an evergreen offer. Each investor is expected to hold a minimum portfolio of six companies with investments typically made over an 18-month period. These will usually be mature private companies, rather than early stage businesses. The main reason for this is the expected risk/return profile: failure rates for more established businesses tend to be lower, and the time to exit typically tends to be shorter, although remember these are still unlisted businesses and capital is at risk.

The Calculus EIS is sector agnostic and the existing portfolio is broadly spread, the aim being to provide diversification. The investment team look for companies with the following characteristics: 

  • Evidence of commercial success, even if the firm is not yet profitable when Calculus invests
  • Primary constraint is access to finance
  • Predictable cash flows and recurring revenues
  • A strong balance sheet
  • A potential to achieve a target IRR of 20% (or a multiple of 2.5× over 5 years). 

Please remember, whilst the aim is a lower-risk portfolio than other growth EIS funds, all EIS investments are by their nature higher risk.

Recent rule changes on EIS have reduced the general number of deals available to EIS investors, but this has not affected Calculus, according to Mr Glencross, because of its focus on growth investing. In his view 80% of companies considered in the past would still qualify under new rules. 

Indeed, Calculus believe it is seeing an unprecedented flow of high-quality investment opportunities. Despite an improving market, banks are still reluctant to lend to SMEs. AIM activity has increased, but focus is on larger companies. This means even excellent, well-managed smaller companies struggle to raise finance for expansion, which is where the Calculus Capital EIS fund can step in.

Most of the deals come via corporate advisers or by the management teams of their underlying companies coming back for a second or third time. 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 500 deals a year, reviews around 150 companies and completes around 7 to 12 investments. 

When reviewing a deal, the team analyses the company’s own forecasts, pulls them apart and compares them to its own forecasts. They consider potential exit strategies before making an investment. Calculus conducts its own comprehensive research then brings in external parties for in-depth due diligence. 

Once investments are made, Calculus aims to mitigate risk by actively managing its portfolio companies. Calculus usually takes a board seat and pays close attention to the firms’ management accounts.

Target return

There is a target return of 2.5× over 5 years. 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. 


Each investor is expected to hold a minimum portfolio of six companies with investments typically made over an 18-month period. 

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

Blu Wireless is one of Calculus' more recent investments. Blu Wireless is a firm leading the way in bringing ultra-fast millimetre wave (mmWave) wireless technology into homes and businesses through the roll-out 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 as part of a £6.6 million institutional and private investment round and follows the recent strategic investment round lead by ARM, the UK semiconductor and software design company. Calculus provided follow-on funding 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.

Chopd – Calculus EISChop’d

Chop’d is a salad bar chain and a pioneer in the healthy eating space. Founded in 2004, Chop’d has a strong commitment to sourcing fresh local ingredients, from Essex barn-reared chicken to sustainable salmon from the Shetland Islands.

Calculus invested £2 million in the business in 2014. The investment has been helping expand the business from nine to 30+ sites across London and the UK. Chop’d has a strong and successful management team with operational experience from Yo! Sushi, Chez Gerard and Pizza Express.

Human Race – Calculus EISHuman Race (example of previous exit) 

Human Race is a mass participation sports company. Human Race organises more than 55 events in the UK, including the London Winter Run, Windsor Triathlon and the new VitalityMove events run in partnership with Olympic champion Jessica Ennis-Hill.

Calculus Capital invested in Human Race in April 2012 and made a profitable sale to Amaury Sport Organisation (A.S.O.), the owner of Le Tour de France in September 2016. The investment was held for 4 years and 5 months.

Origin Broadband (example of previous failure)

As with any high-risk investment, not all turn out well. One such example is Origin Broadband. Originally based in Doncaster, Origin is a national telephone and broadband provider. The company was founded in 2011 and at one point claimed to be the UK’s sixth largest broadband provider. Between 2016 and 2018 the company saw its client base grow from 4,000 to 36,000, however, its operational systems struggled to cope with the rapid increase in demand. By December 2018 the firm had to cut a significant number of jobs as a result of ‘bad debts, increased staff costs and weak cost control’.

Despite a number of proactive measures to curb losses, Calculus decided the company would require extensive funding to support it up to profitability. Consequently, the EIS fund sold its holdings to a private investor resulting in a loss or flat return on investment (depending on tranche).


The manager has to date not supplied performance details in the format used for other EIS offers on this website. 

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 / SEIS investments are high-risk so should only form part of a balanced portfolio and you should not invest money you cannot afford to lose. They also tend to be illiquid and hard to sell and value. Before you invest, please carefully read the Risks and Commitments and the offer documents to ensure you fully understand the risks. 

Tax rules can change and benefits depend on circumstances.

This EIS fund invests in early-stage businesses which are more likely to fail than larger ones. So you should expect a number of failures in the portfolio, or even be prepared for all companies to fail.

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 up to 18 months to fully deploy investor capital following the closing dates. However, it may take longer.

The next tranche deadline for the fund is: 30 April 2021.

Our view

Calculus has the longest track record of any EIS fund but remember, 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
Funds raised / sought
Minimum investment
30 Apr 2021 for next tranche
Last updated: 6 March 2020

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