Add Business Days To Date Calculator

Use this calculator whenever a deadline, delivery date, or schedule milestone is defined as N business days after a known start date.

Enter a start date and how many business days to add. The calculator advances one UTC calendar day at a time, counting only weekdays (Monday through Friday). Saturdays and Sundays are never counted as business days.

The start date is not included in the count—the same rule as the SLA Deadline Calculator's business-day mode and the shared addBusinessDays utility. Adding zero business days returns the start date unchanged.

Optional US federal holiday exclusion uses the same sample holiday list as the Business Days Calculator (2024–2026). When enabled, listed holidays are skipped in addition to weekends.

Start date: Monday 6 January 2025. Business days to add: 10.

Result: Monday 20 January 2025 (10 weekdays forward, skipping the two intervening weekends).

With US federal holidays excluded and 20 January 2025 falling on the MLK Day holiday, the result would shift one weekday later to Tuesday 21 January 2025.

The Business Days vs Calendar Days Guide explains when weekends and holidays count and which day type applies to deadlines, invoices, and contracts.

The How Business Days Are Calculated Guide and Business Days Between Dates Guide cover the counting rules behind every business-day tool on this site.

The Business Days Calculator and Working Days Calculator count weekdays between two known dates, excluding weekends and optional US federal holidays.

The Add Business Days To Date, Subtract Business Days From Date, and Business Day Offset calculators move a single date forward or backward by a business-day count.

The Business Days Until Date Calculator counts business days remaining from today or a custom date to a target deadline.

The Days Between Dates Calculator counts every calendar day between two dates, including weekends—use it instead of the business-day tools when weekends should count.

The Date Range Calculator and Date Duration Calculator break a range into calendar-day totals or a years/months/days breakdown, with inclusive or exclusive boundary options.

The Add or Subtract Days Calculator shifts a single date forward or backward by days, weeks, or months.

The Age Calculator applies the same calendar breakdown used by Date Duration to a birth date, expressed as years, months, and days.

The Hours Between Dates and Date Difference calculators measure elapsed time between two date-times down to hours, minutes, and seconds.

The Date Format Converter, Unix Timestamp Converter, and Timezone Converter handle format and zone conversion for a single instant rather than a span between two dates.