Base periods
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Base periods

Revised March 25, 2011

  1. A base period is a period of time used to determine a spenddown liability and establish a certification period for medically needy coverage.  The client may choose either a three month or six month base period for the current base period.  The current base period begins the first of the month in which the department receives an application for medical benefits or may begin the first of the following month if the client applies late in the month and chooses to withdraw their request for medical coverage in the initial month.
  2. A client may also request medical coverage for the three month period immediately prior to an application for benefits, or any time there is a gap in base periods of three months or less.  The client may choose any or all of the months in the retroactive base period when determining the amount of the spenddown liability.


We receive an application for benefits on March 10th.  The client requests coverage for February only as he was hospitalized from February 15 - February 21.  The client is eligible for coverage for February and does not have other medical expenses for December or January.  Deny December and January coverage and establish a one month retroactive base period for February only.


Children and pregnant women who are found eligible for CN coverage in one of the months of a retroactive base period are continuously eligible for CN coverage for one year in the case of children or through the end of the postpartum period in the case of pregnant women.  Carefully review eligibility for coverage during the retroactive period if the case has trickled to medically needy spenddown coverage in the application month.  If processing a retroactive base period and the client is CN eligible in any of the retroactive months, do not allow any months after the CN approval month to trickle to spenddown. 

Worker Responsibilities

  1. Review the application to determine if the client has applied for retroactive coverage.  If not, contact the client to determine if they have any unpaid or paid medical expenses that they incurred during that time period.  
  2. Explain to the client that they have the option to use the expenses they incurred and paid during the three month period or any expenses they have incurred but which remain unpaid towards meeting spenddown in the retroactive base period, or that they may apply the expenses towards their spenddown liability in the current base period. 
  3. Explain the advantages or disadvantages of both options.  If the client chooses to use expenses that were incurred and paid within the 3 month retroactive period towards the current base period, we cannot then use the expenses towards establishing coverage in the retroactive period at a later date. 
  4. ACES defaults to a six month certification period; however that may not be the best option for the client. If possible, talk to the client to determine their circumstances.  Upcoming hospitalizations or other major expenses may make a difference in selecting a base period.
  • If the spenddown amount is high, a three month base period may be to the client's benefit.
  • If the spenddown amount is low and the client can easily meet it, a six month base period would provide medical coverage for a longer period of time.


A client has $30.00 per month in excess income.

Spenddown in this example would be $90.00 for a 3 month base period and $180.00 for a 6 month base period. 

If the client has $250.00 in qualifying medical expenses, a 6 month base period would be beneficial to the client since they would have a longer period of eligibility.

If the same client has no qualifying medical expenses at the time of application and anticipates no large medical needs, a 3 month base period may be in the client's best interests.  The would enhance the client's opportunity to meet spenddown and obtain coverage. 

Modification Date: March 25, 2011