Sticking to a holiday budget is easier said than done—particularly when consumers' wallets are feeling a bit fatter.
According to a two-part study conducted by advertising technology firm Fluent, 42 percent of consumers surveyed before Thanksgiving said they planned to spend less on holiday gifts this year than they did in 2013.
However, when Fluent revisited the shoppers after Christmas, only 32 percent of respondents said they actually ended up spending less.
What's more, although only 28 percent of shoppers had planned to spend more, 36 percent ended up doing so.
Fluent's study surveyed the same 2,400-plus consumers before and after the holidays.
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"Record low gas prices in December likely contributed to increased spending on gifts this year," said Jordan Cohen, chief marketing officer at Fluent.
But the break at the gas pump likely helped shoppers save on holiday travel. Cohen said that when the firm polled consumers before Thanksgiving, 36 percent said they thought they'd spend less on travel this holiday season. By the weekend after Christmas, 52 percent said they'd actually spent less.
According to a recent study by AAA, Americans saved an estimated $14 billion on gasoline in 2014 as compared with the prior year.
"More money saved at the pump meant more money in their wallets to spend on gifts for loved ones," Cohen said.
Fluent's study also found that shoppers got a later-than-expected start to their holiday shopping. Although 43 percent of respondents said they planned to start shopping in advance of Black Friday, less than 32 percent did so.
The next read on how the holidays are shaping up for retailers will come Thursday, when a handful of names announce their same-store sales for December.
According to ShopperTrak, which tracks in-store purchases by compiling data from retailers' sales logs, November sales increased 5.4 percent compared with the prior year. It has yet to release its December figures.
According to IBM, online sales were 13.9 percent higher year over year in November and December.