| Postcode | Country | County | Type | Status |
|---|---|---|---|---|
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated December 1998 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated June 1998 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | Terminated June 2000 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Large | ||
| England | Hertfordshire | Small | Terminated October 2011 | |
| England | Hertfordshire | Small | ||
| England | Hertfordshire | Small |