Hydrographic Notes allow you to inform us of any navigationally significant information. This information could include new or suspected dangers, changes to navigational aids, amendments to details included in publications and suspicious charts or publications that could be counterfeit.
These can be sent in paper format (as outlined below) or sent using the ADMIRALTY H-Note App.
For emergency information affecting safety of life at sea, forward to:
navwarnings@ukho.gov.uk.
Alternatively, contact T:+44 (0)1823 353448 (direct line) or F: +44 (0)1823 322352.
What to include in Hydrographic Note submissions
The Hydrographic Note forms below contain information to help you complete any submission. These details are also included within Chapter 8 of the Mariner's Handbook (NP100). Please note that you should also contact the originating hydrographic office when navigating on IMO-approved, non-ADMIRALTY nautical charts.
Find out more about the Mariner's Handbook (NP100) >
Downloading and sending Hydrographic Note forms
Each of the a forms below contain accompanying instructions to help you complete any submissions. Simply choose the type of information you'd like to send and download the corresponding form.
H102 - Hydrographic Note (with instructions) for General Information
H102A - Hydrographic Note (with instructions) for Port Information
H102B - Hydrographic Note (with instructions) for GNSS observations against corresponding chart positions
H634 - Ornithological Log
H636 - Marine Bioluminescence Observations reporting form
H637 - Marine Life / Fishing Activity reporting form
Please email your completed form to:
sdr@ukho.gov.uk or by send it via fax:
+44 (0)1823 352561. For urgent information contact F:
+44 (0)1823 322352 or send by email.
Once we’ve received and processed your data, we’ll acknowledge receipt of it by post or email.
Supporting information
Chart images and photographs - sent either with the hard copy or as attachments to the electronic copy - will help us to clarify your report.
Any format is acceptable. Those most commonly used are JPEG, TIF and AutoCAD. File sizes of the Hydrographic Notes range from approximately 61Kb to 70Kb; however the size of a returned email would depend on any additional attachments that have been made.
