5-Day Assessment Window
The 5-day assessment window is the regulatory deadline for completing the start of care comprehensive assessment, including the OASIS: within 5 days after the start of care date, where the SOC date counts as day 0. A parallel 5-day window applies at recertification, when the assessment must be completed during the last 5 days of each 60-day certification period.
How to count the window
For start of care, the SOC date is day 0, and the comprehensive assessment must be completed by day 5. A patient admitted on Monday the 1st has an assessment deadline of Saturday the 6th. The date that proves compliance is M0090, the assessment completion date recorded on the OASIS, which should reflect the day the assessing clinician finished collecting the data. For recertification, the window sits at the other end: days 56 through 60 of the certification period, counting the period's first day as day 1. Both windows are calendar days, weekends and holidays included.
Why CMS gives 5 days at SOC
The window acknowledges that a complete picture of a new patient rarely emerges in one visit. Function fluctuates, medication lists take time to verify, and some items benefit from observing the patient across a couple of encounters. The assessing clinician can gather information over multiple visits within the window, then complete the assessment. In practice, most high-performing agencies finish the SOC OASIS at or immediately after the first visit anyway, because open assessments pile up, recall degrades, and late completion delays the plan of care, QA review, and downstream billing readiness.
What happens when the window is missed
A late comprehensive assessment is a Conditions of Participation compliance problem, and patterns of lateness are the kind of finding surveyors escalate. The assessment still must be completed as soon as the miss is identified, with honest dating: M0090 reflects when the assessment was actually completed, and falsifying it to appear compliant converts a process failure into a documentation integrity problem with far worse consequences. Late assessments also jam the revenue cycle, since QA, OASIS submission, and clean claim preparation all queue behind the completed assessment.
Keeping the window under control
Window misses are almost always workflow problems:
- Track every open admission against its day-5 deadline on a daily dashboard
- Schedule the SOC visit with enough time budgeted to complete the assessment
- Set an internal standard tighter than the regulation, such as completion within 48 hours
- Escalate assessments still open on day 3 to a clinical manager
- Watch weekend admissions, where coverage gaps cause a disproportionate share of misses
Frequently asked questions
Does the 5-day window include weekends?
Yes. The window runs in calendar days, with the start of care date as day 0 and the deadline on day 5. Weekend and holiday admissions get no extension, which is why weekend coverage planning matters.
Can the OASIS be completed over multiple visits?
Yes, within the window. One qualified clinician gathers and completes the assessment, and M0090 records the date it was finished. What is not allowed is assembling the assessment from multiple clinicians' independent answers.
Is there also a 5-day window at recertification?
Yes. The recertification assessment must be completed during the last 5 days of the 60-day certification period, days 56 through 60. Unlike the SOC window, which follows the start of care, the recert window precedes the new period.