That as they try to pass on soaring cocoa costs to customers who are cutting back.
Over the past few years, the industry has enjoyed big profits - as demand for chocolate has held up despite price hikes.
But data shows this trend may be breaking.
It comes as prices for cocoa hit 46-year-highs and sugar prices are near their highest in more than a decade.
Chocolate makers are betting on the traditional resilience of their product to overcome price increases.
Cadbury-maker Mondelez raised its annual revenue growth forecasts last month while Hershey hiked its profit forecast.
But consumers in Europe and North America have already seen price hikes of about 20% in the last two years.
And data shows they're starting to cut back on the chocolate they buy.
Mondelez expects inflation in cocoa and sugar to continue.
In response, the company said it is ensuring it is significantly hedged and continuing to drive productivity.
But after more than two years of higher prices, analysts said retailers are pushing back.
And Mondelez previously pulled Cadbury and Milka bars from a major Belgian supermarket chain after failing to agree on prices.
Mondelez' chocolate sales volume growth has weakened substantially this year.
And data showed Hershey sales volumes increasingly declined during the period as the company hiked prices.
Hershey said it hoped it sales volumes would reverse their current downtrend as it eased off the rate of price hikes.
