Facility, within Trade & Import Finance
Duty deferment guarantee estimator
Most GB importers can run a duty deferment account without a guarantee, but only up to a point. The limit is set by your busiest month, and the waiver is capped at £10,000 a month unless your net assets excluding goodwill are bigger than the waiver. Put in your own figures and this shows the limit to ask for, what the waiver covers, and the guarantee needed for the rest.
How the limit and the waiver fit together
The account limit comes from your busiest month, the waiver from your balance sheet
A duty deferment account lets you pay Customs Duty, excise duty and import VAT once a month by Direct Debit instead of consignment by consignment. You apply with an estimate of the debt, and the account then has a monthly limit. Go over it and, as HMRC puts it, "you will not be able to defer any more duties and import VAT for the rest of that month" (How to use your duty deferment account). HMRC's advice is to have "the correct guarantee or account level for any large import or peak period liabilities", which is why this tool starts from your busiest calendar month, not your average one.
In Great Britain there are two waiver approvals: one for up to £10,000 a month, and one for "a specified amount over £10,000 per month". Both need the business to be UK-established, with no serious or repeated customs or tax infringements and no serious criminal offences related to the business in the past 3 years, and positive net assets excluding goodwill at the application date and for the past 3 years (or the time you've been trading). The higher one also needs net assets excluding goodwill "greater than the value of the waiver you're applying for", at the application date and at the most recent balance sheet date (GOV.UK guarantee waiver guidance).
That second test is where growing importers come unstuck. Deferring more than £10,000 a month with net assets below the waiver doesn't lose the waiver altogether: GOV.UK says you "may still be eligible for a partial waiver of up to £10,000" and will be asked to guarantee the additional amount only.
Worked examples
One importer, eight situations
Example inputs, not market figures. A UK-established company whose busiest month carries £25,000 of Customs Duty, with import VAT going through postponed VAT accounting so none of it is deferred, adds 20% headroom of its own choosing. That makes the limit to ask for £25,000 × 1.2 = £30,000 a month. What happens next depends on the balance sheet, the record and where the goods come in.
| Situation | Monthly limit | Waived or reduced | Guarantee needed |
|---|---|---|---|
| Smaller importer: busiest month £6,000 of duty, clean record | £7,200 | £7,200 | £0 |
| Clean record, net assets excluding goodwill £120,000 | £30,000 | £30,000 | £0 |
| Clean record, net assets excluding goodwill £8,000 | £30,000 | £10,000 | £20,000 |
| Clean record, net assets excluding goodwill £20,000, partial waiver as GOV.UK describes it | £30,000 | £10,000 | £20,000 |
| Same business, if HMRC approved a specified waiver just under its £20,000 of net assets | £30,000 | just under £20,000 | a little over £10,000 |
| Established in the EU, not the UK (GB account) | £30,000 | £0 | £30,000 |
| Northern Ireland account, no AEOC | £30,000 | £0 | £30,000 (CCG) |
| Northern Ireland account, with AEOC | £30,000 | £21,000 | £9,000 (CCG, duty at 30%) |
The £6,000 importer's limit is £7,200 with the same 20% headroom, inside the £10,000 waiver. With £8,000 of net assets no waiver over £10,000 is possible, so the partial waiver of £10,000 applies and £20,000 is guaranteed. With £20,000 the conditions as written would also allow a specified waiver over £10,000 but below net assets; whether HMRC approves one is its decision. In Northern Ireland the AEOC figure is 30% of £30,000, which is the rule GOV.UK gives for Customs Duty in a deferment account covered by a CCG (GOV.UK: apply for a customs comprehensive guarantee).
Your own figures
Estimate your deferral limit and guarantee
Free to use, nothing is saved or sent anywhere. Runs entirely in your browser. The figures start as the worked example above: change them to yours.
Estimate
Waiver of £30,000: no guarantee
| Busiest month | Limit to ask for | Waived or reduced | Guarantee needed |
|---|---|---|---|
| £25,000 | £30,000 | £30,000 | £0 |
- Over £10,000 needs net assets excluding goodwill greater than the waiver, both now and at the most recent balance sheet date, and a PFS1 with supporting documents.
Rules: GB waiver types, conditions and the partial waiver from GOV.UK's guarantee waiver guidance; Northern Ireland CCG requirement and the AEOC 30% rule for Customs Duty from GOV.UK's CCG application guidance. Checked 23 September 2026. The amounts, headroom and fee are yours. HMRC decides the limit, the waiver and any guarantee on your application; this is an estimate to plan with, not a decision. Not tax or legal advice.
Reference table
Guarantee needed at different monthly limits
| Monthly limit | GB, waiver test passed, net assets above the limit | GB, waiver test passed, net assets below the limit | GB, waiver test failed or not UK-established | NI, no AEOC | NI, AEOC |
|---|---|---|---|---|---|
| £5,000 | £0 | £0 | £5,000 | £5,000 | £1,500 |
| £10,000 | £0 | £0 | £10,000 | £10,000 | £3,000 |
| £25,000 | £0 | £15,000 | £25,000 | £25,000 | £7,500 |
| £50,000 | £0 | £40,000 | £50,000 | £50,000 | £15,000 |
| £100,000 | £0 | £90,000 | £100,000 | £100,000 | £30,000 |
Customs Duty only, no headroom. "Net assets below the limit" uses the partial waiver of £10,000 that GOV.UK describes; a specified waiver below net assets, if HMRC granted one, would bring the figure down. Up to £10,000 a month the basic waiver covers the whole limit whatever the net assets figure, as long as it has stayed positive. A GB business with AEOC status needs no guarantee at any of these limits. NI figures assume HMRC confirms the CCG amount as applied for.
What the limit buys you
Up to six weeks between clearance and payment
For Customs Duty and import VAT declared on the Customs Declaration Service, everything deferred in a calendar month is collected on the 16th of the following month, or the next working day if the 16th isn't one. GOV.UK describes that as "between 2 and 6 weeks", "an average of 30 days credit". Excise duty works to a 15th to 14th accounting period with payment on the 29th of the later month (How to use your duty deferment account). A goods consignment cleared on the 1st therefore isn't paid for until the middle of the next month, which is often the difference between paying duty before the goods are sold and after.
If a month runs hot, the Customs Declaration Service lets you make a top-up payment against the account to free up balance; paying online through your bank is usually instant but can take up to 2 hours, CHAPS and Faster Payments by the next working day and Bacs within 3 working days, though GOV.UK currently warns of delays in top-ups reaching the account. HMRC's advice for regular overruns is to raise the guarantee or waiver instead (Top-up your duty deferment account). An existing waiver amount can be increased through the online amendment form, with a fresh PFS1 unless one went to HMRC in the last 3 months or you hold AEOC (Cancel or amend your duty deferment account).
What the tool can't see
Things that change the answer
- Postponed VAT accounting. A VAT-registered importer can account for import VAT on its VAT Return, and GOV.UK says you don't need a deferment account to defer import VAT if you do (GOV.UK). For most VAT-registered importers that takes the largest item out of the limit altogether. It isn't available on some postal imports and simple online declarations (GOV.UK).
- Changes after approval. If your circumstances change so you no longer meet the waiver conditions, GOV.UK says you must tell HMRC without delay and either provide a guarantee or apply to close the account. A year of losses that turns net assets negative is exactly that kind of change.
- Agent accounts. Many importers never hold their own account and clear through a customs agent or forwarder's instead. An agent acting in its own name on your behalf is jointly and severally liable for the customs debt, which is why agents are careful whose imports go through theirs.
- The guarantee itself. Where one is needed in GB, it comes from a UK-established, PRA-regulated financial institution on form C1201, and HMRC says not to send one until it asks. In Northern Ireland, HMRC reviews the CCG application, tells you the amount, and you then get a guarantor to cover it (GOV.UK). The fee is whatever that guarantor charges; the tool only multiplies out a quote you already have.
Sources
- GOV.UK: Check if you can get a guarantee waiver for a duty deferment account in Great Britain
- GOV.UK: Apply for an account to defer duty payments when you import or release goods into Great Britain
- GOV.UK: How to use your duty deferment account
- GOV.UK: Apply for a customs comprehensive guarantee to cover customs debts
- GOV.UK: Customs comprehensive guarantee (CCG)
- GOV.UK: Top-up your Customs Declaration Service duty deferment account
- GOV.UK: Cancel or amend your duty deferment account in Great Britain
- GOV.UK: Check when you can account for import VAT on your VAT Return
- GOV.UK: Guarantee deferment of payment to HMRC (C1201)
Guarantee needed, or the limit keeps running out?
A deferment guarantee is a bank or insurer commitment, and it usually sits alongside whatever else is funding the import cycle. If you've been asked for one, or a peak month keeps pushing you over the limit, tell us what's happening and we'll tell you whether it's something we can help with.
Adam Parker
Founder of Muswell Rose Consulting Ltd, which trades as Established Finance · former Managing Director of Penny, an invoice finance business, working in mortgages, commercial finance and fintech lending since 2010 (career history).
Last reviewed:
Common questions
Questions about this
How much can I defer without a guarantee?
In Great Britain, a UK-established business that passes HMRC's waiver test can defer up to £10,000 a month under the basic waiver. Above that, the waiver can be for a specified amount, as long as net assets excluding goodwill are greater than the waiver, both at the application date and at the most recent balance sheet date. AEOC holders get a waiver at the level of their deferral limit. Northern Ireland accounts always need a customs comprehensive guarantee.
What if I need more than £10,000 a month but my net assets are lower?
GOV.UK says you may still be eligible for a partial waiver of up to £10,000, and you'll be asked to guarantee the additional amount only. HMRC also offers the option of accepting a lower deferral limit when the waiver doesn't cover what you asked for.
Does import VAT count towards my deferral limit?
Only if you defer it. A VAT-registered business can account for import VAT on its VAT Return (postponed VAT accounting) instead, and GOV.UK says you don't need a deferment account to defer import VAT if you use it. Import VAT that goes through postponed VAT accounting doesn't use up any of the deferment limit.
What happens if I go over my limit in a month?
You can't defer any more duty or import VAT for the rest of that calendar month, so further imports have to be paid for another way until the limit is raised or the next month starts. On the Customs Declaration Service you can also make a top-up payment to free up balance. HMRC can suspend or revoke an account whose guarantee level is persistently exceeded, after written notice.
When is deferred duty actually paid?
For Customs Duty and import VAT declared on the Customs Declaration Service, everything deferred in a calendar month is collected by Direct Debit on the 16th of the next month, or the next working day. GOV.UK describes that as between 2 and 6 weeks of credit, 30 days on average. Excise duty runs on a 15th to 14th accounting period, paid on the 29th of the later month.