You only have 4 months left to use this year's vacation days — here are 5 cheap, easy trips to book now

Lake Tahoe
George Rose | Getty Images

Workers in the U.S. took an average 17.2 vacation days in 2017, the highest level in seven years, CNBC reports. However, 52 percent of Americans still did not use their vacation days, based on research by U.S. Travel Association's Project: Time Off. A record 658 million vacation days went unused.

Given that research shows travel can bring happiness and make you more productive, this year, take advantage of your paid time off.

To help you maximize all your vacation time, here are five affordable and easy trips in the U.S. you can take for a quick getaway this fall to use three to five vacation days.

1. San Juan, Puerto Rico

Vacations in Puerto Rico are cheap for fall. Tourist-friendly places on the island, like capital San Juan, have a functional infrastructure and are safe to visit after 2017's hurricanes. A Google Flights search yielded cheap fares as low as $214 round-trip from New York City and $214 from Chicago.

Hotel rates are affordable, many with rates under $200 a night. You can book a double room at Courtyard Isla Verde Beach Resort, right on the beach and fifteen minutes from San Juan by car, for as low as $190 a night. Doubletree by Hilton in San Juan, in the trendy Condando area and walking distance to the beach, has room rates as low as $161 a night.

You can stay in ocean-view Airbnbs for as little as $64 a night, like this one-bedroom apartment.

2. New York City, New York

Compared to summer, it's affordable to fly to New York City in September, October and November, with savings up to $93 on a flight, according to Skyscanner, which looked at the cheapest destinations to fly to this fall. The national yearly average fare to N.Y.C. is $410.43, and fall prices are $317.87. However, a Google Flights search found great deals like $253 nonstop from Los Angeles, and $139 nonstop from Dallas.

HotelTonight, a hotel discount app, features dozens of low-priced hotels in N.Y.C. in its inventory, and it recently unveiled a new feature, Daily Drop, that offers 15-minute flash sales with rooms up to 30 percent off. You can book rooms up to 100 days in advance. A recent deal in New York City was Lord & Moris, a boutique hotel in Times Square. The Daily Drop rate was $107 a night (regular $229). The second night rate on the deal was $70.

When you book a new hotel, you can find amazing introductory rates. The new Aliz Hotel in Times Square, opening in October, is offering rates as low as $145 a night (typically $265 a night).

3. Lake Tahoe, California

Lake Tahoe, on the California-Nevada border, has great deals in fall following its busy summer season, and before skiers descend over winter. There are plenty of outdoor activities in the mountain resort town, like hiking, fishing, rafting and biking, as well as casinos.

Lake Tahoe is about 45-minutes drive from Reno-Tahoe International Airport. On a Google Flights search, roundtrip flights are as low as $208 from N.Y.C. and $187 from Los Angeles. Lake Tahoe is three hours and 30 minutes by car from San Francisco.

Fall rates are as low as $64 a night at Harrah's Lake Tahoe, or $99 a night at the boutique Beach Retreat & Lodge, a popular beachfront hotel with a pier for water activities in South Lake Tahoe.

4. Kansas City, Missouri

Kansas City is home to famous barbecue (with more than 100 joints), a great jazz scene, top-notch museums (like the National WWI Museum) and artsy neighborhoods. A modern trolley that goes through the heart of downtown and connects cool areas and the best attractions, like the Kauffman Center for the Performing Arts, recently debuted and is free. All this adds up to a great if unexpected vacation destination.

The yearly national average airfare to Kansas City is $298, but prices drop up to 15 percent in fall, with national airfare as low as $253, according to Skyscanner, and flights are even cheaper from major cities, like $173 from N.Y.C, $200 from Chicago and $154 from Atlanta when searched on Google Flights.

Opened July 2018, 21C Museum Hotel Kansas City, a luxury hotel that moonlights as an art museum, is still offering grand opening rates through fall, with doubles as low as $170 a night.

Rooms at Crowne Plaza Kansas City Downtown are as low as $158.

5. Nashville, Tennessee

Summer is the busiest time to visit Nashville, when airfare and hotel rates are at its peak, but prices go down considerably in September when people are back to work and school after summer break. Fall is also one of the best times to visit weather-wise.

A search on Google Flights found round-trip flights to Nashville as low as $129 from Atlanta, $188 from N.Y.C. and $213 from Phoenix.

Introductory rates at the new Holston House hotel are as low as $181 until November, or $184 at Courtyard by Marriott Nashville at Opryland for fall.

Don't miss:

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9 places in America you have to see in your lifetime

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