If you're thinking of heading out to the dealership to close the deal this weekend—especially if it's Friday—you might want to hold off. And Saturday? Well, it depends, but unless it's close to the end of the month, you're more likely to get a better deal if you wait until Monday or Tuesday.

And this isn't purely anecdotal. The pricing-intelligence firm TrueCar has a team of analysts looking at historical sales data and specific transaction prices in the past (from a database of more than 300,000 vehicle sales), weighing those trends with current pricing, incentives, and market demand, to predict what will happen again over the next period, typically 30 days.

For instance, in TrueCar's last analysis of the best and worst days to buy a cars, covering February 16 through March 18, the firm predicted that February 27 would offer the highest projected discount (6.52 percent), while next Friday, March 12, will offer the lowest average discount (5.45 percent).

That's more than a $400 difference on a $40,000 vehicle.

Jesse Toprak, TrueCar's vice president for industry trends, said that these predictions start with simply looking at what happened in the past, every day of the year. "There's a very strong pattern of seasonality," Toprak said, so it's a good indication that these strong or weak days will repeat. "What's happened in the past plays a role."

Toprak offers this general advice on which days are better than others:

• Toward the end of the month is usually better. Many dealerships still have monthly sales bonuses and other targets to meet, so the general trend is that there are better deals on offer late in the month.
• Major holiday weekends are windows of opportunity. Dealerships will often spend more money on advertising and have special sales drives on holiday weekends (not religious holidays though), considering the extra shopping day to offer a better return on their investment. The hope is that shoppers will make their follow-up purchase visit the same weekend they took their test-drive. And mood is a part of it: "Shoppers tend to be in a better mood, and that makes more sales," said Toprak. Presidents' Day recently was a good one; Memorial Day will be the next.
• Monday mornings are a good time to shop. Toprak said that if he were shopping, he'd probably go on a Monday (or weekday) morning, not a weekend. "Salespeople will want to get the week started on a good note," he said. And if you're the only one in the showroom, that's VIP treatment, right?
• Saturdays are a wild card. Sometimes shoppers get a better deal on Saturdays, other times not. Dealerships tend to be crowded with shoppers on Saturdays, so it's easy for a salesperson to just let you go if you try to lowball them. On the other hand, no matter how crowded it is, some dealerships will reward Saturday sales, such as a bonus for selling three cars on Saturday, so if you get the right person at the end of a Saturday afternoon, who knows?
• May flowers with good deals. Among months, May might be one of the best to get a good deal, as dealer stock is typically strong and traditionally automakers have considered the month to be a make-or-break time for sales.

Of course, if you're well armed with information before you head to the dealership—in the way of customized TrueCar market pricing, which is available at TheCarConnection.com—the day shouldn't matter, Toprak points out.

While the data on what days are better than others is useful, it should just be a starting point, Toprak argues, and it's just one of many pieces of information that you take into consideration when shopping for a vehicle. "Ten minutes of work before you go to the dealership can get you similar or better deals any day of the month."

TrueCar recently had several of its staff go to dealerships to purchase several mainstream models, including the Honda Accord, Volkswagen Jetta, and Chevrolet Equinox, along with several premium models, including the Audi A4, BMW 3-Series, and Porsche Cayenne, and found that they were able to negotiate an average final price of about $1,800 less when armed with a price report.

Taking advantage of the over-the-Web, up-front no-haggle price quotes that some dealerships now offer might actually be the best way to skip the up-day, down-day patterns or being at the mercy of whatever fickle salesperson is manning the showroom.

"There's no need to stress out about negotiating. Go somewhere with up-front pricing," and know your numbers, Toprak advises.

And if you really want to maximize your savings, it probably wouldn't hurt to mind the day you go.

[TrueCar]

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