A permanent resident is a person who has been granted permission to reside and work for a period of time throughout the United States. As proof of permanent residence status, the person receives an identifying document or authorization card that is often referred to as Form I-551. Form I-551 is believed to last for 10 years. It must be renewed prior to the expiration date. 

Reputable green card lawyers can help you with the green card renewal process Although they don't come with an expiration time, the law requires that all cards update to the latest version. The most recent green cards come with an expiration date and must be renewed every ten years, as they will force the USCIS to enhance the card with more options like updating the pictures to guard against fraud.

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If the form I-551 is obtained by marriage to an US Citizen or a permanent resident, it's known as the Conditional Green Card. The Conditional Permanent Residence lasts for two years and has to be renewed prior to the expiration date for the conditional resident. To eliminate the condition on the residence, the form I 751 is used.

Permanent Green Card holders whose green cards have expired or are scheduled to expire in the near future must renew their green card. If they fail to fill out the form I-551, in time, they might face difficulties when working or be prevented from re-entry into the United States until a new card is issued, or be denied access in other benefits, and be deemed to be out of status.