Insurance companies were hit hard by the EU referendum. Despite the market’s rapid rebound, shares in both Standard Life (LSE: SL) and Legal & General Group (LSE: LGEN) are still worth less than they were before the UK’s Brexit vote.

Both companies have published their interim results today, so I’ve taken a closer look at the figures. Are investors’ fears justified, or are these 6% dividend yields a great buying opportunity?

Profits up 22%

Legal & General shares fell by 5% this morning, despite the £12bn firm reporting a 22% increase in net profit.

The savings and insurance firm said that net cash generation rose by 16% to £727m during the first half of the year, while earnings per share were 24% higher at 11.27p. Return on equity — a key measure of profitability — rose slightly to 20.4%, compared to 19.1% during the first half of 2015.

Legal & General’s annuity assets rose by 18% to £51.0bn during the first half of the year. Assets under management rose by 18% to £841.5bn, although net inflows of £9.6bn were lower than the £13.8bn reported for the same period last year.

Why are the shares falling?

Investors remain concerned about the potential impact of an EU departure and some of the potential risks in Legal & General’s equity and bond portfolios. The company has done its best to reassure investors. It issued a detailed financial statement immediately after the referendum, confirming the strength of its finances.

Today’s results confirm these claims. Legal & General reported a regulatory Solvency II coverage ratio of 158% today, and a solvency surplus of £5.3bn. Although those figures are slightly lower than the firm’s 2015 year-end figures of 169% and £5.5bn, they remain well within acceptable limits. They aren’t a cause for concern, in my view.

Indeed, I rate Legal & General as a strong long-term income buy at current levels. The firm’s cash generation remains impressive and should cover this year’s expected dividend of 14.1p.

After today’s fall, Legal & General trades on a forecast P/E of 10 and with a yield of 6.8%. I remain a buyer.

Standard Life looks cheap too

It’s a similar story at Legal & General’s smaller rival, Standard Life. The firm said this morning that operating profits jumped 18% to £341m during the first half of the year. That’s 9% ahead of analysts’ forecasts of £314m.

Standard Life also trumpeted a sharp rise in assets under management, which rose by 7% to £328bn. However, net inflows of new cash were just £4.1bn, which is less than the £7.4bn reported for the same period last year.

The interim dividend has been increased by 7.5% to 6.47p. Standard Life reported underlying earnings per share of 13.5p for the first half of the year. This suggests that the group is on course to hit full-year earnings forecasts of 26p per share.

Standard Life’s shares have risen by nearly 5% following today’s results. They now trade on a 2016 forecast P/E of 12.8 and with a potential yield of 6%. I’d still be happy to buy, although Legal & General remains my preferred pick in this sector.

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Roland Head owns shares of Legal & General Group. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.