It's official: The OOO alerts are clearing from your inbox and Q4 budget meetings are landing there instead. As you toast goodbye to summer vacation, retailers are also clearing out their inventories to prepare for a new season. Here's how you can take advantage of these summer-to-fall deals.

What to Buy in September

Patio furniture. Department stores and furniture outlets are slashing prices on outdoor furnishings, in some cases up to half off, says Sara Skirboll, shopping and trends expert at RetailMeNot. Translation: Act now to upgrade your al fresco experience with new dining sets, seating and décor. Don’t forget a few blankets and throws to make your space truly transitional.

Outdoor grills. If your grill is on its last leg after hosting all those summer barbecues (um, where was my invite?), then good timing — now’s the time to get a new one for cheap. Savings average about 20% off, Skirboll says. If you’re loyal to a specific brand or model, shop earlier in the month. Selection becomes more limited — though prices might be lower — as fall approaches.

Home appliances that can’t wait. New models of major home appliances, like ovens and washer-dryer sets, move onto sales floors this month. Current models will be marked to move — meaning those of us who don’t really care about the latest and greatest dishwasher can save up to 40% on last year’s model. That said, if you can wait a few months, bigger discounts on home appliances might roll around for Black Friday. Two exceptions: refrigerators, which go on sale in May, and air-conditioning units, which are cheapest in the winter.

A new-to-you iPhone. Every Apple-phile you know is eagerly awaiting the tech giant’s annual event. But while those jumping on the newest products will pay up for early adopter status, the September product announcement will also bring markdowns on last year’s iPhone models. TBD on what that’ll mean for the iPhone X’s headline-making price tag ($100 off old versions is the norm), but it’s worth keeping tabs if you’re ready for an upgrade.

Mattresses. Buy now or forever hold your peace. The two best times to buy a mattress are long weekends in the summer: Memorial Day and Labor Day. In addition to product markdowns, negotiate for perks like free delivery, removal of your current mattress or price-matching on competing offers. Expect discounts at 50% off or more, Skirboll says.

Coffee. Is there a better discount than free? Mark your calendars for National Coffee Day on September 29 (yes, it’s a thing). Last year, your faves, including Dunkin’ Donuts, Tim Hortons and Peet’s Coffee, offered freebies, buy-one-get-one deals and discounted coffee beans.

What to Skip in September

Electronics. With the exception of Apple products, you’ll want to hold off on any other new gadgets for a month or two. “Electronics in general won't be at their lowest price point until Black Friday and Cyber Monday,” Skirboll says.

Denim apparel. If you’re the type to dream of sweater weather and booties as soon as pumpkin-spice-everything hits the shelves, at least hold off on buying your new jeans. Fall fashions, especially denim, see significant markdowns in October during mid-season sales.