| Postcode | Country | County | Type | Status |
|---|---|---|---|---|
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated March 2003 | |
| England | Hertfordshire | Small | Terminated April 2018 | |
| England | Hertfordshire | Large | Terminated March 2009 | |
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated January 2009 | |
| England | Hertfordshire | Large | Terminated December 1999 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated September 2015 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated May 2004 | |
| England | Hertfordshire | Small | Terminated September 2014 |