Date of last delinquency

The date when you last missed a regular monthly payment

The date of last delinquency shows up on your credit report, a document that outlines your credit history and current credit. Even if you make a partial payment of a debt, the creditor can still report you to a credit bureau as delinquent. Some creditors report a delinquency right away, others do not. Often you can negotiate with a creditor to get a more flexible pay back plan before they report you as delinquent.

"The significance of the referenced dates is based on the credit report periods set forth in the FCRA.  The FCRA sets specific periods for adverse items reported to your credit report, after which they can no longer continue to be included in your CR.

Those dates are based on the date of occurence of the type of adverse item, not upon when they are reported or any subsequent action on the part of the one who reported it.

For monthly OC account delinquencies, they must cease to be included in your CR after 7 years from their date of occurence.  Date of account opening, last reporting, etc., are irrelevant.  It is your record of your activity on the OC account that sets those dates.

Collections and charge-offs have their own peculiar date for CR exclusion, which is based on ONLY one date... the date of first delinquency on the OC account that led to the collection or charge-off.  The DOFD is fixed by your first delinquency in the most recent chain of account delinquencies with the OC preceding the charge-off or collection.

Here is a sample of how DOFD works:

30 late   4/2005      this initially sets the DOFD at 4/2005

60 late   5/2005      DOFD remains 4/2005 account paid back into good-standing   

6.2005    DOFD remains 4/2005

.....pattern repeats through the last chain of delinquencies.......last chain:

30 late    2/2006     this resets the DOFD to 2/2006, as a new chain of delinquencies begins

60 late    3/2006     DOFD remains 2/2006

90 late    4/2006     DOFD remains 2/2006

120 late  562006     DOFD remains 2/2006

Charge-off   6/2006     DOFD remains 2/2006

Collection    9/2007     DOFD remains 2/2006

Under this example, both the charge-off and the collection are required to be excluded from the consumer's credit report after 8/2013 (7 years plus 180 days from DOFD).

DOFD is not required to be reported to the CRA until such time as a charge-off or collection referral is reported.  Thereafter, any party reporting any information on the charged-off or collection debt must provide the DOFD to the CRA.

If you do not have a charge-off or collection reported,there will most likely be no reported DOFD in your credit file."

Source:  http://ficoforums.myfico.com/t5/General-Credit-Topics/date-of-last-activity-vs-date-of-first-delinquency/td-p/1244495