# Blocked Numbers Parameters

When you export your blocked numbers, or prepare a file to import them in bulk, Cloud Voice reads and writes a CSV (comma-separated values) file with three columns. Each row in the file is one blocked-number entry. Use the reference below to fill every column correctly and to understand which values are accepted.

## Field reference

| Column | Required | Accepted values | Default |
|--------|----------|-----------------|---------|
| `Name` | Yes | Up to 127 characters. | None |
| `Type` | Yes | `inbound`, `outbound`, or `both` (see below). | `inbound` |
| `Number` | Yes | Digits, letters, and the characters `[` `]` `*` `#` `(` `)` `.` `-` `+` `!`. Separate multiple numbers or patterns with `&`, for example `{number1}&{number2}`. | None |

All three columns are required for every row. If any is missing, that row can fail to import.

:::tip
The simplest way to get the columns and formatting exactly right is to export your existing blocked numbers first, edit or add rows in that file, then import it back. Starting from an export means the column order already matches what the import expects.
:::

## Type values

The `Type` column sets the direction of the block. PBX (Private Branch Exchange) here means your Cloud Voice phone system:

- `inbound`, stops the listed number or numbers from calling into your phone system.
- `outbound`, stops your extensions from placing calls to the listed number or numbers.
- `both`, applies the block in both directions: the number cannot call in, and your extensions cannot call out to it.

:::note
If you leave the `Type` column empty for a row, Cloud Voice fills it in with the default value, `inbound`.
:::

:::caution
An `outbound` or `both` block stops every extension on the account from dialing the listed number. Review the list before you import so you do not accidentally block numbers your users still need to reach, and never add emergency service numbers (such as 911) to an outbound block.
:::