Costco bargain hunters are going to have to pay an additional $5 to $10 annually as the popular warehouse chain prepares to raise its membership fees for the first time in seven years. The company disclosed the forthcoming 8% increase in the fee as part of a monthly sales report this week, per the AP. The new fees, set to take effect Sept. 1, will boost the price of Costco's basic Gold Star membership from $60 to $65 annually, while the cost for the premium Executive membership will rise from $120 to $130. With inflationary pressures squeezing household budgets, Costco's 700 "warehouse" locations across the US and Canada have become more popular shopping destinations. That, in turn, has helped boost profits, making the company's stock a hot commodity among investors. Costco's shares have nearly doubled during the last 18 months, increasing the company's market value by about $180 billion during that span.