Credit Suisse shares sank to a new low Monday on fears about the ability of banks to hang onto deposits following the collapse of Silicon Valley Bank.

Shares in the Swiss lender fell as much 15%, to 2.12 Swiss francs, according to FactSet data. The cost to insure its five-year debt rose to 450 basis points, meaning it would cost 450 euros to insure €10,000 of the bank's senior debt against default for a year, according to S&P Global Market Intelligence data.

Credit Suisse was already under pressure in recent months. Customers, mainly wealth clients, withdrew $120 billion in the three months to Dec. 31 because of worries about its financial health.

The bank has tried to reassure investors with a restructuring plan. It raised $4 billion in new shares last year to give it a bigger cushion to absorb ongoing quarterly losses.

Unlike SVB, Credit Suisse has little in the way of held-to-maturity bonds on its books according to Jefferies analysts. Most of its loan book is in ultra-conservative Switzerland.

(By Margot Patrick)