The simple trick I'm using to save over $500 on my bills

Nearly 25 percent of millennials in the U.S. still live with their parents and I happen to be one of them. Like other 20-somethings who grew up and stayed in New York, I'm already saving a lot on rent, but there's another way I've managed to cut expenses by living at home: joining family plans to lower my bills.

Here's how much I plan to save on my phone, Netflix and Spotify bills by teaming up with my own family.

Spotify

I've been subscribed to the music streaming service Spotify Premium since 2012 and, as a student, I used to pay $5 month for it. After finishing my master's degree in 2016, I begrudgingly started paying the full price of $10 a month — until I realized I could save money by looping in my family.

Spotify Premium for Family costs $15 a month and can support up to five separate accounts, as long as each person lives under the same roof. My parents, sister, brother-in-law and I now pay $3 a month. Spotify is a bit strict about splitting a premium subscription and requires each person to create his or her own profile and confirm they live at the same address. I don't know what happens if you try inserting a different address, so proceed with caution.

What I'll save on Spotify
Price of a single premium account: $9.99 a month over 12 months = $119.88
Price of a five-person premium account: $14.99 a month over 12 months = $179.88
What I'm now paying (after splitting costs): $3 a month over 12 months = $36
Savings this year: $83.91

Netflix

Netflix currently allows up to five different members of your household to set up a personalized profile on the same account. Given that my older sister has had a Netflix subscription since 2006 and she only shares it with her husband, I asked if I could glom on and chip in to her bill. The monthly cost is usually $10.99 in total, so I contribute $3.66 a month.

This works primarily because my sister and I live under the same roof, but you could potentially share an account with your roommates and trusted friends who don't live with you. About 20 percent of adults ages 18 to 24 say they borrow passwords from people who don't live with them to access streaming sites such as Netflix, HBO Now or Hulu. Technically, though, personal Netflix accounts are intended only to be shared with people within a given household.

What I'll save on Netflix
Price of owning an account: $10.99 a month over 12 months = $131.88
What I'm now paying: $3.66 a month over 12 months = $43.92
Savings this year: $87.96

Phone bill

My family has been using AT&T for as long as I remember but we made the switch to Verizon this summer, since Verizon has better service coverage where we live and offered a better deal on an unlimited data plan. Instead of paying $75 for a single unlimited phone plan for myself, I now pay $45 for the same service as part of the family plan. Given the savings I was getting on the plan, I negotiated a deal with my mom to take advantage of Verizon's buy-one-get-one-free offer, so instead of paying $810 for one iPhone 8 Plus, we each paid $405 and got our own phones.

You can also reap these benefits by splitting a family phone plan with friends but be aware that may come with its own set of complications.

What I'll save on my phone plan
Price of single phone plan: $75 a month over 12 months = $900
What I'm paying: $45 a month over 12 months = $540
Savings this year: $360

It has been three months since I switched to combined plans and I've already saved $133. By the time I hit the 12 month mark, I'll have saved a total of $531.87.

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