| Postcode | Country | County | Type | Status |
|---|---|---|---|---|
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated April 2008 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated March 2002 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated August 2019 | |
| England | Hertfordshire | Large | Terminated December 2008 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated December 1998 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated December 1990 | |
| England | Hertfordshire | Large | Terminated September 2000 | |
| England | Hertfordshire | Large | Terminated May 2001 | |
| England | Hertfordshire | Large | Terminated January 2001 | |
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Large | Terminated July 2006 |