Date attributes are used to represent a single calendar year, month and day, independent of timezone. Attio exclusively works with the ISO 8601 format, i.e. YYYY-MM-DD e.g. 2023-11-24. There is only one default example of a date attribute, foundation_date on the company object. Date attributes can only be single-select.

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Reading values

Date attributes have a single property, value (a string). 
{
  "active_from": "2023-04-03T15:21:06.447000000Z",
  "active_until": null,
  "created_by_actor": {...},
  "attribute_type": "date",
  "value": "2023-11-24"
}

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Writing values

Date values can be written by passing an ISO 8601 date string. If hours, months, seconds or timezones are provided, they will be trimmed. For example:
  • '2023' → '2023-01-01'
  • '2023-01' → '2023-01-01'
  • '2023-01-02' → '2023-01-02'
  • '2023-01-02T13:00' → '2023-01-02'
  • '2023-01-02T14:00:00' → '2023-01-02'
  • '2023-01-02T15:00:00.000000000' → '2023-01-02'
  • '2023-01-02T15:00:00.000000000+02:00' → '2023-01-02'
If a timezone is provided that would result in a different calendar date in UTC, the date will be coerced to UTC and then the timezone component will be trimmed. For example, the value '2023-01-02T23:00:00-10:00' will be returned as '2023-01-03'. As date values are always single-select, you may write values either by passing the date string directly, or by wrapping a single value in an array. You may also write date values using an object with a single value key. 
{
  "foundation_date": "2004-07-29"
}

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Filtering

Date attribute values can be filtered by their value. You can filter for an exact date using the implicit syntax, or use the $eq,$gt,$gte,$lt,$lte operators with the explicit syntax. 
{
  "filter": {
    "foundation_date": "2023-11-24"
  }
}