A customs letter of authorization is a signed document in which you, the shipper or importer, give a broker, courier or other agent permission to handle customs matters for a shipment on your behalf. A customs power of attorney does the same job with more formality. Which one you need depends on the country the goods are entering or leaving, so this guide explains the difference, lists what to put in the letter, and shows what to check before you ship from Singapore.
TL;DR
- A letter of authorization lets an agent act for you at customs. In some countries the law asks for a formal power of attorney instead, or accepts a letter only if it meets set requirements.
- A good letter names both parties, states what the agent may do, identifies the shipment or a time period, and carries signatures and a date.
- You stay responsible for the information declared, even when an agent files it for you.
- Rules differ by country, so check the customs authority of the destination (and of Singapore for export) before you sign anything.
- When you book with a courier platform, the shipping documents are normally generated for you, but you still supply accurate details.
Table of Contents
- What a customs letter of authorization is
- Letter of authorization vs. power of attorney for customs
- When you need to authorize someone at customs
- What to include in your letter
- A simple template you can adapt
- How to sign and submit it
- Check that an authorization is valid and limited
- Shipping from Singapore: what to check
- Common mistakes to avoid
- Our perspective
- Ship from Singapore with the paperwork handled
- FAQ
- Sources
What a customs letter of authorization is
Customs authorities deal with the person responsible for the goods: the importer, the exporter or the "principal". Most people do not file declarations themselves. They use a customs broker, a freight forwarder or a courier. For that agent to speak to customs in your name, you need to give written permission.
That written permission is what people call a letter of authorization (LOA), authorization letter or customs clearance authority. It usually does these things:
- Identifies you and the agent.
- States the customs tasks the agent may carry out.
- Says which shipments or what period it covers.
- Shows that you, not the agent, are granting the permission, through your signature.
You may be asked for one when you ship through a broker, when a courier needs to clear a consignment for a recipient, or when a company wants a named employee or third party to collect cargo.
For a wider view of how customs fits into a shipment, see our guide to the role of customs in shipping.
Letter of authorization vs. power of attorney for customs
The two terms overlap, and in everyday shipping they are often used for the same thing. The difference is the legal weight and the formality.
| Letter of authorization | Customs power of attorney | |
|---|---|---|
| Typical use | Simple, often one-off permission to clear or collect a shipment | Standing or formal authority for an agent to transact customs business |
| Format | Free-form letter or the agent's own template | Often a prescribed form or a document that meets set legal conditions |
| Scope | Usually one shipment, a few shipments or a set period | Can be limited (specific transactions) or general (all customs business) |
| Revocation | Often by simply telling the agent in writing | May require formal written notice to the customs authority |
| Who asks for it | Couriers, forwarders, brokers | Customs brokers and customs authorities |
The United States shows how formal a customs power of attorney can be. Under 19 CFR 141.31, a principal may give a limited or general power of attorney covering some or all of its customs business. Under 19 CFR 141.32, the document may be CBP Form 5291 or an equivalent document executed in the same manner. The same subpart covers revocation by written notice and extra conditions for nonresident principals, including a resident agent who can accept service of process.
So in the U.S., a casual note saying "please clear my parcel" is not the same as a customs power of attorney for a broker. In other countries, a plain letter may be all that is needed. When someone asks you for an "authorization letter", ask which one they mean and whether they have a required format.
When you need to authorize someone at customs
You are likely to need written authority in these situations:
- You ship commercial goods and a broker files the declaration. The broker acts in your name, so the broker needs your authority.
- You are the importer and a courier clears the parcel for you. Many couriers ask for authority to act as your agent for clearance and duty payment.
- Someone else collects your cargo. A freight forwarder, warehouse or terminal may want a letter naming the person who may pick it up.
- You are a business sending regular shipments. A standing authorization, valid for a set period, saves you from signing a new letter each time.
- You are a nonresident importer. Some countries have extra requirements for foreign principals.
Four official examples show how this works in practice:
- In the United Kingdom, GOV.UK guidance says an appointed customs representative cannot act without your written instructions. Those instructions must say whether the representative acts directly or indirectly, and you remain responsible for due diligence on the declarations made.
- In Canada, the CBSA's Memorandum D1-6-1 says that for commercial goods imported under section 32, the written authority must identify the parties and transactions, state whether sub-agents are allowed and for how long, and carry both parties' signatures and an effective date.
- In Saudi Arabia, the Zakat, Tax and Customs Authority describes broker authorization as letting a customs broker complete customs procedures for an importer or exporter. It can be limited to import, export or both, and to one or several uses.
- In Taiwan, Customs publishes an official sample letter of authorization that lets a broker handle specified matters. These include verifying examination results, paying duties, taxes and fees, receiving notices and collecting cargo or samples.
The pattern is the same everywhere: written, signed, specific about who and what. The details change by country.
What to include in your letter
Use the destination customs authority's or your agent's required format if one exists. If you are free to write your own, include the following. These are the elements that official examples above tend to require or sample.
The parties
- Your full legal name or company name, address and any tax or customs identification number.
- The agent's full name, address and licence or registration number if they have one.
Use the exact name that appears on your commercial invoice and shipping documents. A mismatch between names is a common reason a clearance stalls.
The authorized activities
Say plainly what the agent may do. Examples include:
- Preparing and submitting customs declarations.
- Paying duties, taxes and fees on your behalf.
- Receiving notices from customs.
- Collecting the cargo or samples after clearance.
- Dealing with inspection or examination requests.
Only list what you want the agent to do. A narrower letter is safer than a broad one. If your agent only needs to clear one parcel, do not authorize "all customs business". For a sense of how these tasks look in another market, UK customs rules for importing walks through declarations, duty payment and related steps.
The scope: shipment or period
Choose one:
- Single shipment: give the waybill or tracking number, invoice number, origin, destination and a short description of the goods.
- Period: give a start date and an end date, such as "valid from 1 January to 31 December".
If the country allows sub-agents, say whether your agent may appoint one. If not, say so.
Validity and revocation
State when the authority starts, when it ends and how you can withdraw it. Where the law sets a revocation method, follow it. In the U.S., for example, a customs power of attorney is revoked by written notice received by CBP, as described in 19 CFR Part 141, Subpart C.
Place, date and signature
- City and date of signing.
- The signatory's printed name and title (for companies).
- A handwritten or valid electronic signature, and a company stamp if your market uses one.
A simple template you can adapt
Copy the wording below into a document on your letterhead and adjust it to the destination's rules. It is a starting point, not legal advice.
Letter of Authorization
Date: [date]
I/We, [full name or company], of [address], [tax or customs ID], authorize [agent name], of [address], [licence or registration number if any], to act as my/our agent for the following customs matters: [prepare and submit declarations / pay duties and taxes / receive customs notices / collect cargo].
This authorization applies to: [shipment reference, invoice number and description of goods] / [period from date to date].
The agent [may / may not] appoint sub-agents. This authorization may be withdrawn by written notice to the agent.
Signed: [name, title, signature, company stamp]
If the destination requires a prescribed form, use that form and treat this letter as a supporting note only.
How to sign and submit it
- Ask the receiving party what they need. The broker, courier or customs office may have its own template. Using it avoids rejections.
- Fill in every field. Blank lines, missing ID numbers and unclear scope slow things down.
- Sign it correctly. For a company, the signatory should be someone with authority to bind it.
- Send it the way the agent asks. That might be an upload to a shipping platform, an email attachment or a paper copy. Some customs systems also keep the authority on file with the agent rather than filing it with the authority.
- Keep a copy. You may need it if there is a query about who declared the goods.
Check that an authorization is valid and limited
Before you sign, and again after, run through these checks:
- Is the agent who they say they are? Where a licence or registration number applies, confirm it with the relevant authority.
- Does the scope match the job? The letter should not allow more than the shipment needs.
- Are dates sensible? An open-ended authority that never expires is hard to track.
- Is the signatory right? Someone without authority to sign for a company can make the letter invalid.
- Can you revoke it? Know the method, and use it when the relationship ends.
Remember that the authority transfers the work, not the responsibility. The UK guidance above makes this point directly: the trader stays responsible for due diligence on what is declared. Provide accurate invoices, correct descriptions and honest values, however the declaration is filed.
Shipping from Singapore: what to check
Most parcels leaving Singapore need no letter from you at all when you book through a courier or platform, because the carrier handles customs formalities as part of the service. A letter becomes relevant when you use a separate broker, when you ship commercial goods in volume, or when the destination country asks for proof that you appointed an agent.
Work through these points:
- Export side. Singapore Customs explains on its declaring agent authorisation page how you can authorise a declaring agent, including permission to use your bank accounts for direct payments to Customs. If you declare through an agent, set this up before the shipment. Our guides on the Singapore export license and TradeNet codes and the export permit and HS checks cover the permit side.
- Import side. The destination customs authority sets the rules for the person receiving the goods. Look up its page on appointing an agent, as the UK, Canada and Saudi Arabia examples above each do it differently.
- Declaration details. Your documents drive the declaration. Our guide on what you need for a customs declaration in Singapore lists them.
- Fees. If a broker clears the goods, a handling charge may apply. See who pays the brokerage fee on a courier shipment.
- Personal items. Moving belongings has its own rules. Read what "personal effects" means for shipments before you describe them on a form.
For businesses, the shipping documentation process and how to prepare shipments for export show where an authorization letter fits among the other papers. If you work through a forwarder, what freight forwarding is explains what that agent does for you.
Common mistakes to avoid
- Using a template from another country without checking it. Many sample letters online are written for a specific nation's customs law.
- Leaving the scope vague. "All shipments" or "all customs matters" gives away more than most senders intend.
- Mismatched details. Names, addresses and ID numbers should match your invoice exactly.
- No end date. Set one, or define the single shipment it covers.
- No signature or an unauthorized signatory. The letter must be signed by someone entitled to sign.
- Forgetting the copy. Keep one for your records.
Our perspective
Most senders do not need to become customs experts. They need documents that are accurate and an agent who acts only within the authority given.
We built Simply Parcel around that idea. When you book through us, you compare priority, connect-plus and economy options, book a free pickup at your door, and get shipping labels and customs documentation generated automatically. That removes much of the paperwork that makes people reach for an authorization letter in the first place.
Where a letter or a formal power of attorney is still required, our advice is to keep it narrow, name the shipment or period, and match every detail to your invoice. We offer guidance on restricted goods and customs requirements, so you know what applies before the parcel leaves.
SP
Ship from Singapore with the paperwork handled
If you are sending a parcel or documents abroad, Simply Parcel lets you compare rates, book a free pickup and get your labels and customs documents generated for you. You choose between priority, connect-plus and economy speeds, track the shipment in real time, and add optional protection coverage. There is no monthly volume commitment.
Get a quote and book your shipment, or see the shipping options.
FAQ
Is a letter of authorization the same as a power of attorney for customs?
Not always. A letter of authorization is usually a simple, specific permission, while a customs power of attorney is a more formal document that may be limited or general. In the U.S., the rules in 19 CFR Part 141 set out accepted forms, including CBP Form 5291. Other countries accept a plain letter, so ask the agent which one they require.
Do I need a customs authorization letter to ship a parcel from Singapore?
Usually not for a standard parcel booked through a courier platform, since the carrier prepares the customs paperwork. You may need one if you use a separate broker, ship commercial goods, or the destination authority asks you to appoint a representative. Check the destination customs authority's page before you ship.
Who should sign the letter?
The principal, meaning you as the individual shipper or importer, or an authorized signatory if you act for a company. The agent receiving the authority usually signs too where the rules require both parties, as in Canada's written authority for commercial imports under Memorandum D1-6-1.
How long is a customs authorization valid?
It is valid for what the letter says: one shipment or a defined period. Some countries require the duration to be stated. You can withdraw it in writing, and in the U.S. a customs power of attorney is revoked by written notice received by CBP.
Can I authorize someone to collect my cargo?
Yes. A letter naming the person and the shipment reference, signed and dated, is the usual way. The Taiwan Customs sample letter, for instance, covers cargo collection among its listed matters. The party holding the cargo may have its own form.
Sources
- eCFR: 19 CFR Part 141, Subpart C, Powers of Attorney
- GOV.UK: Get someone to deal with customs for you
- CBSA Memorandum D1-6-1: Authority to Act as an Agent
- Zakat, Tax and Customs Authority: Customs Broker Authorization
- Taiwan Customs: Letter of Authorization sample
- Singapore Customs: Declaring Agent Authorisation