2 of the market's top growth stocks to consider before the ISA deadline

City stockbroker Numis(LSE: NUM) is one of London's champion growth stocks. Over the past five years, the shares jumped 144% excluding dividends as earnings surged eight-fold.

And I don't believe this growth is set to come to an end any time soon. City analysts are expecting earnings growth of around 5% for 2018, and a similar rate for 2019 as Numis continues to win clients.

Indeed, Numis recently toppled JPMorgan Cazenove from its long-held position as the most popular stockbroker in the City, adding 70 corporate clients to its books since 2010 as JPMorgan's roster fell by a quarter.

Beating the market

In a trading update today, Numis said it has "delivered a strong first half" and is expecting "to report revenue and profits significantly ahead of the comparable period." Capital Markets and M&A activities have been strong thanks, in part to "higher average deal fees" while Corporate Broking & Advisory has "delivered revenue materially higher than the first half of the prior year."

It looks to me as if Numis is firing on all cylinders and is well on the way to meeting City growth forecasts for the year. That said, it did warn today that first-half performance is "below the record performance achieved in the second half" of 2017, although the introduction of the MiFID II regulation earlier this year is responsible for some of the disruption. Numis is not alone here as MiFID II has caused confusion across the financial services industry.

Still, it looks to me as if it is on track to report another strong year. But despite the firm's outlook, and record of growth, shares in the company still look cheap.

Undervalued growth

Last time I covered it, I calculated that the stock was trading at a cash-adjusted forward P/E of 10.2 and it does not look as if much as changed.

With the City expecting the firm to earn 27p per share for 2018 and a net cash balance of £96m at the end of September 2017, I calculate that the shares are currently trading at a cash-adjusted forward P/E of 10.1, a valuation that looks too good to pass up.

Keeping it in the family

Another growth stock I believe that you should include in your ISA is property company Henry Boot(LSE: BOOT).

Property construction is a cyclical business, and generally, these companies do not make for good long-term investments.

However, Henry Boot has been in business for 132 years and is still family managed. The secret to the firm's longevity seems to be its conservative business model. As my Foolish colleague, Roland Head pointed out last week, the company's net debt declined from £32.9m to £29m last year, giving a gearing level of just 11%, indicating to me that this business has a robust balance sheet designed to weather market downturns.

Henry Boot also reported last week that group sales for fiscal 2017 rose 33%, while pre-tax profit climbed 40% to £55.4m. Chairman Jamie Boot said the firm has a "strong pipeline" for 2018 with positive customer sentiment continuing to support sales growth. Since 2013, profits have risen 280%.

Nevertheless, despite the bright outlook and conservative balance sheet, shares in the company trade at a relatively depressed 10.7 times forward earnings. In my opinion, the shares deserve at least a market average multiple of 13.7.

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Rupert Hargreaves owns no share mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.