Confirmation effective date of maritime Declaration for Temporary Storage (ATO)

Publication date 17-11-2025, 15:47 | Last update 17-11-2025, 16:17 | News

Do you bring goods into the EU by sea from outside the EU? By 1 October 2026, you must submit your declaration for temporary storage (ATO) via the Single Window for maritime and air transport (SW) using new system specifications.

What will change for you?

There are two changes:

• The effective date for the new ATO has been postponed from 1 October 2025 to 1 October 2026. You may continue to submit the current ATO until that date.
• The system specifications are being updated. These are expected to be available around 1 March 2026.

You will continue to submit the ATO via the Single Window (SW), only according to new system specifications. Software suppliers refer to this system as the Trade and Transport Gateway (HTG).

New system specifications

The system specifications for the maritime ATO have already been published on the portal for software developers. These system specifications are associated with the MIG Single Window and are subject to change. This is changing:

• Maritime declarants can submit the ATO in two ways:
  • a TSD message containing master and house data;
  • a TSD message containing only master data.
• The TSR (Temporary Storage Reuse) message will no longer be provided as a way to submit an ATO to Dutch Customs. You may no longer reuse data from the ENS when submitting an ATO in the future.

The new system specifications for the TSD will be developed in the coming months and published around 1 March 2026 via the portal for software suppliers.

Why this change?

The new date (1 October 2026) gives you more time to prepare for the transition. Until then, you can continue to submit the current ATO as usual.

The adjustment of the system specifications provides you with more options for fulfilling your reporting obligations. This reduces the risk of logistical delays caused by an incorrect ATO.

The new ATO system specifications are required due to the implementation of the Union Customs Code (UCC). The new system specifications align the data in the ATO with that in the ENS.

Further information

The Dutch Customs National Helpdesk (NHD) can assist you with questions about the ATO and provide technical support.

Would you like to know more? Watch the webinar Changes to Entry and Temporary Storage Maritime (available in Dutch only).

The Questions and answers about Release 3 ICS2 page provides answers to frequently asked questions about this release