Marie Kondo teaches folding Boston Globe | Getty Images

Marie Kondo's guiding principles — holding onto what brings you joy and letting go of the rest — can also apply to your paperwork. "This is another category of items that you should be dealing with," said Tony Steuer, author of "Get Ready! A Step-by-Step Planner for Maintaining Your Financial First-Aid Kit." "If you do it that way, it makes it a little more approachable as part of your greater tidying up." However, despite the temptation to clean house, there are some things you shouldn't get rid of, he said. And since chances are, none of it sparks joy, here's a guide to determine what to keep and what to toss.

Keep

You should hold onto marriage certificates, separation or divorce papers, birth certificates, current passports, medical records, insurance policies (for as long as they're active), wills, Social Security cards, diplomas and transcripts, adoption and custody papers. The same goes for your car title, registration and repair records, mortgage deeds, real estate bills of sale, receipts for home improvement projects, property appraisals and an itemized inventory of your household goods in case you ever need to settle an insurance claim. For that reason, also keep receipts for large purchases like rugs, jewelry and artwork, as proof of their value. Those items can all be kept indefinitely and in paper form, according to Janet Alvarez, executive editor of Wise Bread.

The general rule of thumb is to keep tax returns, receipts for large purchases, pay stubs, brokerage summaries, credit card statements, settled student loan records and terminated rental agreements for up to seven years — the statute of limitations from the IRS. However, these items can all be stored electronically to reduce physical clutter. The IRS can audit your returns for up to three years after you file if it determines you may owe additional tax, six years if it believes you underreported income by 25 percent or more and up to seven years if you file an incorrect claim for a capital loss from a worthless security or have bad debt.

Toss

"There's a misunderstanding that you need to keep all of your receipts," said Monica Sipes, a senior wealth advisor at Exencial Wealth Advisors in Frisco, Texas. "With the new tax law, those receipts are piling up for no good reason." The Tax Cuts and Jobs Act eliminated personal exemptions and nearly doubled the standard deduction to about $12,000 for singles and $24,000 for married joint filers — which will likely result in fewer people taking itemized deductions on their 2018 returns. If you were hoarding those proof of purchases in a shoebox with the hope of claiming a big break on your 2018 taxes, that can all be cleared out now — along with any other financial documents older than seven years. Whatever you do get rid of should be shredded to protect your personal information, Alvarez advised. She suggests shredding those documents at a local public school or library.

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