| Postcode | Country | County | Type | Status |
|---|---|---|---|---|
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated September 2020 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated December 1991 | |
| England | Hertfordshire | Large | Terminated December 1994 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | Terminated May 1994 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated December 1981 | |
| England | Hertfordshire | Large | Terminated December 1994 | |
| England | Hertfordshire | Large | Terminated May 2008 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small |