| address | Email Address |
| addresses | Add address fields to message |
| after.envelope | Append children to message |
| as.address | Create an address object |
| as.character.address | Convert address object to character |
| as.character.envelope | Create formatted message. |
| as.character.header | Create formatted header. |
| as.character.MIME | Convert MIME object to character vector |
| attachment | Add attachments to a message object |
| bcc | Add address fields to message |
| c.address | Concatenate address objects |
| cc | Add address fields to message |
| cleave | Split a compound address object |
| comments | Add or query comments of message. |
| compare | Compare vectors |
| compliant | Tests whether an email address is syntactically correct |
| cutoff | Set or query message expiry or reply-by time |
| display | Extract display name |
| domain | Extract domain of email address |
| encrypt | Encrypt or sign a message |
| envelope | Create a message. |
| expires | Set or query message expiry or reply-by time |
| format.address | Encode email addresses in a common format |
| from | Add address fields to message |
| gmail | Create a SMTP server object. |
| html | Add an HTML body to a message object. |
| id | Set message ID. |
| importance | Add fields for message importance and priority |
| inreplyto | Add In-Reply-To and References header fields |
| keywords | Add or query keywords of message. |
| length.address | Length of address object |
| local | Extract local part of email address |
| mailersend | Create a SMTP server object. |
| mailfence | Create a SMTP server object. |
| mailgun | Create a SMTP server object. |
| mailtrap | Create a SMTP server object. |
| message_id | Create a message ID |
| mime-parameters | Parameters for MIME functions |
| normalise | Normalise email address |
| parties | Extract sender and recipient(s) |
| precedence | Add fields for message importance and priority |
| print.address | Print an address object |
| print.envelope | Print a message object |
| priority | Add fields for message importance and priority |
| qp | Quoted-Printable encoding |
| qp_decode | Quoted-Printable encoding |
| qp_encode | Quoted-Printable encoding |
| raw | Extract raw email address |
| receipt | Request read or delivery receipts |
| references | Add In-Reply-To and References header fields |
| render | Render Markdown into email |
| reply | Add address fields to message |
| replyby | Set or query message expiry or reply-by time |
| request_receipt_delivery | Request read or delivery receipts |
| request_receipt_read | Request read or delivery receipts |
| response | Add In-Reply-To and References header fields |
| return_path | Add address fields to message |
| sender | Add address fields to message |
| sendgrid | Create a SMTP server object. |
| sendinblue | Create a SMTP server object. |
| sensitivity | Set or query message sensitivity |
| server | Create a SMTP server object. |
| signature | Encrypt or sign a message |
| smtpbucket | Create a SMTP server object. |
| subject | Add or query subject of message. |
| template | Add message body from template |
| text | Add a text body to a message. |
| to | Add address fields to message |
| validate | Validate email address |
| zeptomail | Create a SMTP server object. |