Inventory-linked and non-inventory-linked ports — what it changes when importing into the UK

Inventory-linked UK port — one-line definition

An inventory-linked port is a UK port where the terminal manifest (the electronic list of goods sitting in the arrival shed) is digital and tied to the CDS customs declaration through a so-called Community System Provider — an independent IT operator for the terminal. HMRC describes the mechanism at GOV.UK — Inventory-linked imports: the CSP holds the manifest, the broker files a declaration referencing the UCR/MUCR, HMRC validates it and notifies the CSP, and the CSP issues the release note to the terminal automatically. Without that release the goods stay on inventory hold.

A non-inventory-linked port is the opposite — usually a RoRo port, with no CSP and no electronic manifest layer. Clearance runs purely on direct GVMS: the haulier creates a GMR with MRN and transit references, the driver scans the GMR at the border, and the system returns Cleared or Call to Inspection. With no CSP layer there is no automatic mapping to a manifest, because in RoRo there is no arrival shed in the classic sense — the trailer rolls off the ferry straight onto the road with no stop at a container terminal.

Which UK ports are inventory-linked and which are non-inventory-linked — current map

The split comes from port history and cargo type. Inventory-linked UK ports (all with their own CSP):

• Felixstowe — CSP: MCP Destin8. The UK's largest container port, roughly 40% of national volume. Fully electronic integration with CDS.
• Southampton — CSP: CNS Compass. The UK's second container port, mainly DP World Southampton and ABP Southampton.
• London Gateway (DP World) — CSP: MCP Destin8. A modern deep-sea terminal on the Thames.
• Tilbury (Port of Tilbury London) — CSP: MCP Destin8. Multipurpose port — containers, RoRo, bulk.
• Liverpool (Peel Ports) — CSP: MCP Destin8. Main port on England's west coast.
• Teesport, Hull, Grimsby, Immingham, Harwich — CSP: MCP Destin8 or CNS Compass depending on the terminal.
• Heathrow, Manchester Airport, East Midlands Airport, Stansted cargo — inventory-linked cargo airports with a CSP (mostly CCS-UK).

Non-inventory-linked UK ports (GVMS only, no CSP):

• Dover (Port of Dover) — the UK's largest RoRo port. No CSP, GVMS-only for freight. We cover the flow in detail in Dover vs Felixstowe — which port to pick.
• Folkestone (Eurotunnel / Getlink) — RoRo rail tunnel, 35-minute crossing. Non-inventory, GVMS-only.
• Holyhead — RoRo port handling Dublin traffic. Non-inventory.
• Stranraer / Cairnryan — Scotland-to-Northern Ireland ports (Belfast, Larne). Non-inventory.
• Fishguard, Pembroke Dock — Wales-to-Ireland ports (Rosslare). Non-inventory.
• Poole, Portsmouth (RoRo terminals) — mixed status: some RoRo terminals non-inventory, some container sections inventory-linked.

HMRC publishes the authoritative port list with statuses as part of CDS documentation — Goods location codes for Data Element 5/23 of the Customs Declaration Service (each location code carries an inventory/non-inventory flag). In our day-to-day work we always check this list on a first declaration from a new port, because codes and flags change several times a year.

Community System Provider (CSP) — Destin8, CNS, MCP — how the middle layer works

A CSP is a private company providing IT services to UK ports and airports — it holds the electronic manifest of goods in the arrival shed and ties it to the HMRC declaration. Three CSPs dominate the UK:

• MCP Destin8 — operator: Maritime Cargo Processing (now MCP plc, owned by Descartes Systems). Covers Felixstowe, London Gateway, Tilbury, Liverpool and most Peel Ports terminals. Service details: Destin8 — MCP plc.
• CNS Compass — operator: Community Network Services (owned by ABP — Associated British Ports). Mainly Southampton, Thamesport, Immingham, Hull and some Grimsby terminals. Service: CNS Compass — Community Network Services.
• CCS-UK — airfreight specialist (Heathrow, Manchester, East Midlands). Not relevant for sea import.

From a broker's point of view the CSP is a second login next to CDS. You file the import declaration in CDS (that is HMRC), but for the terminal to hand over the container the CSP needs to "see" the release and issue the release note. That happens automatically if the UCR/MUCR on the CDS declaration matches the CSP manifest. If it does not match, the broker logs into the CSP portal, checks the manifest, corrects the reference and forces a re-match. In a normal flow that takes 30–90 minutes. In a bad flow — half a day with a very irate driver sitting outside the terminal gate.

Comparison table — inventory-linked vs non-inventory-linked UK ports

The table below puts the two models side by side on seven operational axes. This is the only table in the article — but if you understand what sits in it, you understand 80% of the topic:

In short: inventory-linked is the "you are visible in the terminal system" model. Non-inventory-linked is the "you are only visible in the HMRC system" model. The first gives you an extra buffer and an audit trail, at the cost of a layer of complexity. The second is simpler but unforgiving, because there is nowhere to catch mistakes before the gate.

Clearance timing — how a CSP shifts the critical moment

At an inventory-linked port such as Felixstowe the CDS declaration is normally filed pre-arrival — up to 30 days before the ship's planned arrival. The CSP holds the declaration in "awaiting arrival message" status, and once the vessel docks and the shipping line sends the arrival notification to the terminal, the CSP automatically pairs the declaration with the manifest. If everything matches, HMRC performs risking (automatic risk assessment) and the CSP issues the release note. The client sees Cleared before the container even comes off the ship. That is why large import flows through Felixstowe hit roughly a 95% first-pass success rate.

At a non-inventory-linked port such as Dover the critical moment is different. The CDS declaration goes to HMRC usually 2–6 hours before the lorry reaches the ferry gate in Calais/Coquelles. The haulier gets the MRN, adds it to a GMR in GVMS, and the driver heads to France. At the UK gate (Dover or Folkestone Eurotunnel) the driver scans the GMR — GVMS answers Cleared (around 95% of cases) or Call to Inspection (around 5%). We cover GMR in detail in GMR number in GVMS — how to get one. The critical moment: if anything is wrong with the declaration, you find out at the UK gate, not at the French port.

That is a difference that reshapes the working day. At Felixstowe the broker has 7–14 days to fix an issue if the CSP flags it before arrival. At Dover the broker has minutes if GVMS flags a Call to Inspection. In that second scenario the driver goes to an IBF (Inland Border Facility), where they can wait 2–24 hours for an HMRC decision. That is why at Dover we push so hard on clients to deliver a complete document pack at least 12 hours before the lorry leaves PL — every error caught before departure is an hour saved later.

Manual entry — when inventory-linked turns into a nightmare

Manual entry at an inventory-linked port comes up when the CSP cannot map the UCR/MUCR against the manifest. Typical scenarios:

• Groupage without proper UCR consolidation — with consolidated loads the MUCR has to mirror the house bill of lading structure exactly. We cover this in GVMS groupage — GMR for consolidated loads. If the forwarder issued a MUCR with an incomplete HBL list, the CSP throws an inventory mismatch and you have to file manual entry at the terminal offline.
• Ad-hoc port-of-entry change — the ship was meant to call at Felixstowe but, because of congestion, ends up at London Gateway. The destination CSP has no declaration with a UCR matching its manifest — the broker has to refile with a correct location code (DE 5/23).
• MUCR or terminal location code error — a typo in a UCR (hard to catch because it is a 35-character string) means the CSP will not match. The broker sees "awaiting arrival" in CDS while the CSP sees no declaration at all.
• Shipment delisted from the vessel at the last minute — if the shipping line drops the container from the manifest (typically: roll-over to the next vessel), the CSP holds an empty slot and the broker has to cancel the declaration or refile.

In each of these scenarios the broker logs directly into the CSP portal (Destin8 or CNS Compass), looks up the container by number, checks the manifest status and tries to force a re-match. If that fails, they call the terminal inventory team. This is the work clients pay a premium for in the per-declaration rate — EasyClearance Team keeps dedicated channels to the inventory teams at Felixstowe, Southampton and London Gateway for exactly this kind of exception.

Non-inventory-linked — why RoRo is faster but less forgiving

In non-inventory-linked RoRo the flow collapses to three steps: pre-lodge CDS → GMR in GVMS → scan at the gate. No CSP means no middle layer — GVMS reads declaration status from CDS directly and replies to the driver in seconds. That is the design that lets Dover handle 12,000 lorries a day. Every second of gate dwell is another kilometre of tailback on the A20.

The price of that speed: zero buffer. If the declaration has an error, the driver knows five seconds after scanning the GMR. The most common exceptions at non-inventory-linked ports:

• Call to Inspection (CTI) — the driver is routed to an IBF (Sevington for Dover/Folkestone, Ebbsfleet for Eurotunnel loads). A documentary check is usually 2–4 hours, a physical check 8–24 hours. GOV.UK sets out the current IBF locations and procedure at GOV.UK — Attending an Inland Border Facility.
• GMR invalid — the driver has a GMR but one of the MRNs has expired (declaration cancelled) or is not in cleared-for-departure status. The driver has to return to Calais or sit at the border while the forwarder fixes it.
• Wrong route / wrong port — the GMR was raised for Dover but the driver ends up at Eurotunnel (or the other way round). GVMS does not match, the driver has to turn back.

That is why for RoRo loads the EasyClearance Team keeps a 24/7 WhatsApp line (+44 7404 091 503) — a Dover exception needs a reaction in minutes, not hours. At an inventory-linked port you have time for a morning coffee before the call to the terminal. At Dover you take the call standing up.

What it changes for the freight forwarder — operational consequences

For a Polish freight forwarder planning UK shipments the port of entry drives the whole operating model:

1. Deep-sea container from Asia/Africa/USA → target Felixstowe, Southampton or London Gateway. Inventory-linked, CSP, pre-arrival submission. The broker needs a login to the CSP for that port.
2. LCL/groupage from the EU via an intermediate EU warehouse → container typically goes to Felixstowe or Southampton. Inventory-linked, watch the MUCR — groupage is the single most common cause of manual entry.
3. FTL RoRo PL/DE/NL → Calais → Dover/Folkestone → non-inventory, GVMS-only, GMR before departure from Calais. The broker needs a tight pre-lodge workflow (minimum 6 hours before the lorry leaves PL).
4. FTL via Holyhead/Dublin or Stranraer/Belfast → non-inventory, GVMS, and separately consider the Windsor Framework for Northern Ireland (see the Windsor Framework article).
5. Air cargo to Heathrow/Manchester Airport → inventory-linked (CCS-UK), deep integration with the air forwarding system.

For each of these flows the EasyClearance Team keeps a separate playbook. We do not treat Dover like Felixstowe, or the other way round — they are different worlds and need different operational habits. For a broader view of UK ports see UK ports — Dover, Felixstowe, Southampton, a good starting point for anyone new to UK imports.

What it changes for the haulier — CSP work vs GVMS work

A haulier (road carrier) has different tasks in each of the two models. In an inventory-linked flow the haulier does not usually see the CSP directly — the container is released from the terminal against the CSP release note, not by the haulier. The driver arrives at the gate, shows the booking reference, the terminal checks release status and hands over the container. The haulier does need a terminal account (Felixstowe Terminal Operating System, DP World portal and so on) — but that is a separate layer from the CSP.

In a non-inventory-linked flow the haulier is an active participant in GVMS. They create the GMR, they link the MRNs supplied by the broker, they are responsible for getting route and port right. If the broker has not sent the MRNs in time, the haulier cannot close the GMR and the driver cannot leave. We cover haulier registration in GVMS haulier registration — how to use it.

That is why a Polish haulier running imports through Dover has to build an SOP pre-departure checklist: (1) full MRN set from the broker at least 4 hours before departure, (2) GMR created and verified at least 2 hours before departure, (3) the driver has the GMR QR code on their phone before boarding. With an SOP like that Call-to-Inspection risk drops below 5% and every case is manageable, because there is a time buffer.

What it changes for the customs broker — tools and competencies

A customs broker in the UK needs two independent "competency muscles" depending on the ports they handle:

• For inventory-linked: CDS login plus CSP login (Destin8, CNS Compass), knowledge of terminal location codes (DE 5/23), the ability to force a UCR re-match, contacts in the inventory teams at Felixstowe, Southampton and London Gateway. For a general CDS flow overview see Customs clearance — export to the UK.
• For non-inventory-linked: CDS login plus a working pre-lodge flow (automated submission at least 6 hours before the lorry leaves), haulier coordination in GVMS, 24/7 exception cover, a working knowledge of the IBF network. We compare the two worlds in RoRo clearance vs standard port.

A broker who only handles one port type does not understand the other — and clients feel it. A "Felixstowe-only" broker defaults to pre-arrival, which is too late for Dover. A "Dover-only" broker does not know how to log into Destin8 and check a manifest. The EasyClearance Team has operators with experience on both models — our operational setup assumes every broker knows at least two inventory-linked ports (Felixstowe + Southampton) and two non-inventory (Dover + Holyhead).

Transit (T1/T2) at inventory-linked vs non-inventory-linked ports

A specific case: a shipment in transit (NCTS / Common Transit Convention, T1 or T2) that enters the UK through a port and continues to a UK destination, or onwards to the EU (re-export). At an inventory-linked port the transit is discharged on entry at the Office of Destination (that port's code), and only then is the inventory released for collection. At a non-inventory-linked port the transit is also discharged at the Office of Destination, but without the CSP layer — NCTS discharge confirmation goes straight from CDS/NCTS.

In practice, for firms running T1 transit EU → UK via Dover, you first discharge NCTS at Dover (Office of Destination) and only then raise the GMR for the actual import clearance. These are two separate steps that need to be sequenced correctly — otherwise the GMR returns invalid. GOV.UK sets out the NCTS flow at GOV.UK — New Computerised Transit System (NCTS).

How EasyClearance Team handles both port types — 2026 practice

Our operational setup, worked out over several years with Polish importers:

1. Port triage at briefing — on first contact we ask: what container/trailer, origin, which UK port. The answer drives the whole downstream flow.
2. Inventory-linked flow — for Felixstowe/Southampton/London Gateway/Tilbury we pre-arrival submit to CDS the moment we receive the BL from the client. We verify the manifest via CSP login 24 hours before arrival.
3. Non-inventory-linked flow — for Dover/Folkestone/Holyhead we pre-lodge to CDS at least 6 hours before the lorry leaves PL. MRNs go to the haulier the moment the declaration is accepted. We verify the GMR jointly with the haulier.
4. Exception handling — 24/7 WhatsApp +44 7404 091 503. We handle manual entry in a CSP as standard during UK office hours 07:00–19:00, out of hours only for existing customers on an emergency SLA.
5. Client reporting — for inventory-linked the client gets C21 and H1 after release, plus a CSP screenshot showing the release note. For non-inventory-linked the client gets a GVMS status screenshot plus C88/H1.

Different workflow for different ports, same backbone — transparency, full documentation, fast reaction to exceptions. Our per-declaration rates are in the EasyClearance 2026 pricing list — for Standard/Business/Enterprise, separately for import, T1 and Regime 42.

Related topics in the EasyClearance Knowledge Base

Cluster E (UK ports and logistics) is worth reading in full if you are planning a steady UK import flow:

• UK ports — Dover, Felixstowe, Southampton — the cluster pillar, an overview of the top UK ports.
• Dover vs Felixstowe — which port to pick — RoRo vs container, routing choice.
• GMR number in GVMS — how to get one — detailed GMR flow for non-inventory-linked.
• GVMS groupage — GMR for consolidated loads — MUCR, consolidation, manual entry.
• GVMS haulier registration — how to use it — haulier setup for RoRo.
• GMR number and the UK GVMS system — GVMS basics.
• RoRo clearance vs standard port — operational comparison.
• No GMR at the UK border — urgent playbook — exception response.

Official sources

• GOV.UK: Inventory-linked imports — GOV.UK / HMRC, 2026
• GOV.UK: Goods location codes for Data Element 5/23 of CDS — GOV.UK / HMRC, 2026
• GOV.UK: Register for the Goods Vehicle Movement Service (GVMS) — GOV.UK / HMRC, 2026
• GOV.UK: Attending an Inland Border Facility — GOV.UK / HMRC, 2026
• GOV.UK: New Computerised Transit System (NCTS) — GOV.UK / HMRC, 2026
• MCP Destin8 — Maritime Cargo Processing — MCP plc (Descartes), 2026
• CNS Compass — Community Network Services — CNS (ABP), 2026

Frequently asked questions (FAQ)

What is an inventory-linked UK port?

An inventory-linked UK port is a sea port or cargo airport where the terminal manifest (the electronic list of goods in the arrival shed) is linked to the CDS customs declaration through a Community System Provider (CSP). The UK has three main CSPs: MCP Destin8 (Felixstowe, London Gateway, Tilbury, Liverpool), CNS Compass (Southampton, Thamesport, Immingham), and CCS-UK (air cargo — Heathrow, Manchester). Once HMRC releases the declaration, the CSP issues the release note to the terminal automatically and the container can be collected.

Which UK ports are non-inventory-linked?

The non-inventory-linked UK ports are mainly the RoRo ports: Dover, Folkestone (Eurotunnel / Getlink), Holyhead, Stranraer, Cairnryan, Fishguard, Pembroke Dock. They have no CSP — the whole clearance runs on direct GVMS with a GMR (Goods Movement Reference). The driver scans the GMR at the gate and GVMS returns Cleared or Call to Inspection in seconds. Poole and Portsmouth are mixed (some RoRo terminals non-inventory, some container sections inventory-linked).

How do CSPs (Destin8, CNS Compass, MCP) differ from GVMS?

A CSP (Community System Provider) is a private port IT operator — it holds the terminal manifest and ties it to the CDS declaration. It runs at inventory-linked ports (Felixstowe, Southampton, London Gateway). GVMS (Goods Vehicle Movement Service) is HMRC's state system for RoRo — the haulier creates a GMR linking MRNs and transit references, and the system returns status at the gate. CSP = terminal layer (manifest + release note), GVMS = border layer (GMR + status). At an inventory-linked port you use CDS + CSP; at non-inventory you use CDS + GVMS.

Is Felixstowe inventory-linked?

Yes — Felixstowe is the UK's largest inventory-linked port, handling roughly 40% of national container volume. CSP: MCP Destin8 (operator: MCP plc, now owned by Descartes Systems). Full electronic integration with CDS — declarations filed pre-arrival up to 30 days before the vessel, automatic release note once HMRC clears. A broker handling Felixstowe needs a Destin8 login, knowledge of terminal location codes (DE 5/23) and a working grasp of UCR/MUCR flow for deep-sea containers.

Is Dover inventory-linked or non-inventory-linked?

Dover is non-inventory-linked — the UK's largest RoRo port, handling around 12,000 lorries a day. No CSP, the whole flow runs on direct GVMS. The haulier creates the GMR with the MRN from the broker, the driver scans it at the gate and GVMS returns Cleared or Call to Inspection. Call to Inspection routes the lorry to IBF Sevington (the Inland Border Facility for Dover/Folkestone), where the check runs 2–24 hours. The critical moment is pre-lodging CDS and creating the GMR at least 2 hours before the lorry leaves Calais.

When is manual entry needed at an inventory-linked port?

Manual entry at an inventory-linked port becomes necessary when the CSP cannot automatically map the UCR/MUCR to the terminal manifest. Typical scenarios: (1) groupage without proper UCR consolidation — the MUCR does not mirror the HBL structure, (2) ad-hoc port-of-entry change — the ship is diverted to a different terminal, (3) MUCR error (a typo in the 35-character UCR), (4) a shipment delisted from the vessel at the last minute (roll-over). In every case the broker logs into the CSP directly (Destin8 or CNS Compass), checks the manifest and either forces a re-match or refiles the declaration with a correct location code.