|Expected date in the future when a construction will be finished and feature will be opened. Use YYYY-MM-DD format.|
|Used on these elements|
|Status: de facto|
|Tools for this tag|
An approximated date in the future when a construction will be finished and object will be opened, used for example on landuse=construction, highway=construction or building=construction. It is recommended to additionally add check_date=*, which describes the date in the past, when the value of opening_date=* was actually checked.
Date format compatible with ISO 8601: YYYY-MM-DD (year-month-day).
For example: opening_date=2024-08-09 – 9 August 2024
Remember that this date should be a future date; to record when a feature was actually opened or created, use start_date=*.
Avoid combinations such as building=yes + opening_date=future as this would break lots of existing software (see trolltags). This can be avoided by using a lifecycle prefix like construction:building=yes or the specific methods established for roads and railways.
Opening dates in the past should be resurveyed as either construction completed or opening date changed:
- Osmose report for overdue opening
- Overpass API query for overdue openings locally
- Sophox query for overdue openings globally
Opening vs completing construction
In some cases only construction end date is signed, while actual opening date may be later and unknown.
The distinction may apply in cases where there is an additional lengthy legal process of verifying and certifying construction and in cases where actual use depends on segments taking longer. For example a motorway may be completed and unusable as a motorway junction on its East end is still being constructed and for now it leads nowhere.
construction:end_date=* is in some use