When a catalogue base does not carry the story you need to tell, custom formulation is the route: your own active combination, your own scent, your own positioning across several markets. It is also the route that consumes the most time and the most cash before anything ships. This roadmap sets out the four phases, what has to be true before each one starts, which decisions cannot be deferred, and where custom projects most often lose a quarter.
When Custom Development Is the Right Answer
Custom development is justified by one of three conditions, and by nothing else. The first is proven velocity: an ODM SKU is already repurchasing and the constraint on growth is differentiation rather than demand. The second is a retail or distribution agreement that requires an exclusive formulation. The third is a regulatory or performance requirement that no catalogue base satisfies - a specific active level, a claim only a bespoke system can support, or an ingredient restriction in a target market.
If none of those three applies, a catalogue base is almost always the better decision, and our minimal viable SKU guide explains why starting narrower usually produces a stronger second year. Custom development does not make a product better; it makes a product more specific, and specificity only pays when you know who is buying.
Phase 1 - Brief and Feasibility
A brief that says gentle, natural and premium has not been written yet. A usable brief states the target animal and coat or skin type, the use occasion, the claim you intend to make, the pH and active targets in numbers, the pack and fill volume, the price tier, and every market you intend to enter. Each of those decisions constrains the chemistry, and moving one later usually moves all of them.
Feasibility is the phase where a formulator tells you which requirements conflict. A high active level may not survive the preservation system you want; a fragrance-free claim may rule out the botanical extract the marketing team has already written into the product name; a pH chosen for the claim may be wrong for the animal. Expect one to two weeks for this alignment, and expect the brief to change once.
Phase 2 - Prototyping and the Evaluation Loop
Prototyping usually produces two or three candidate formulas rather than one, because the useful comparison is between approaches rather than between versions of the same approach. The evaluation has to run against the brief, not against preference, and it has to include the animal and the owner as well as the bench - a formula that performs and is refused by the dog has failed.
Budget two or three iteration cycles for anything complex: a mousse, a gel, an emulsion or an oral product. Each cycle costs calendar time, so the discipline that matters is deciding what you are testing before the samples arrive. Our OEM versus ODM contract guide is worth reading in parallel, because the ownership position you want shapes how much of this work you fund in a bespoke direction.
| Attribute | How it is assessed | A pass looks like | A common failure |
|---|---|---|---|
| Performance | Bench test on the substrate named in the brief | Meets the brief at the stated use rate | Works only at twice the intended dose |
| Sensory | Owner or panel trial in the real use occasion | Accepted by the animal and tolerated by the owner | The animal refuses it, or the owner dislikes the texture |
| Stability indicators | Accelerated condition with early timepoints | No separation, pH drift or colour change | Separation appears at the first timepoint |
| Pack compatibility | Product stored in the final pack and dispenser | No migration, leakage or change in dose | The actuator clogs or the tube deforms |
Source: formulation development practice; ISO 22716:2007 documentation structure.
Phase 3 - Stability, Safety and Challenge Testing
Nothing gets committed to a commercial batch before the test programme is complete. Accelerated stability at elevated temperature and humidity, together with real-time data, establishes the shelf life you print; freeze-thaw confirms the pack survives distribution; the preservative challenge confirms the system controls microbial growth. For oral and leave-on products, add a review of every ingredient against the actual exposure route rather than against a rinse-off assumption.
The programme differs by format, and treating it as one universal checklist is how products reach the wrong conclusion. A rinse-off shampoo and an enzymatic cleaner both need a challenge test, but only the cleaner needs retained-activity measurement at each timepoint, and only the leave-on spray needs substrate compatibility work. The documentation structure for all of it follows ISO 22716:2007, and our preservatives and shelf life guide covers the preservation decisions in more depth.
| Product type | Stability | Preservative challenge | Additional safety work |
|---|---|---|---|
| Rinse-off shampoo | Accelerated plus real time | Required, aqueous system | Irritation and sensitisation assessment |
| Leave-on spray | Accelerated plus real time | Required | Substrate compatibility and inhalation consideration |
| Oral gel or spray | Accelerated plus real time | Required | Ingredient review against swallowed exposure |
| Enzymatic cleaner | Accelerated plus real time | Required for aqueous systems | Retained activity measured at every timepoint |
Source: test programme design for companion animal care products; OECD test guideline framework.
Phase 4 - Scale-Up and the First Commercial Batch
Scale-up is where a laboratory formula meets a filling line, and the differences are physical rather than chemical: mixing shear, order of addition, transfer losses, fill accuracy and the behaviour of the product in a hopper. A pilot batch at production scale is the cheapest way to discover that a formula which pours in a beaker will not pump through a nozzle.
Three documents should exist before the commercial run: a specification with numeric ranges and test methods, a batch record structure that the line actually follows, and an approved reference sample held under defined conditions. If the pilot and the commercial batch disagree, the reference sample is the arbiter. Our standard ODM minimum is 1,000 pieces per SKU for catalogue bases, with a bespoke formula quoted per project because the pilot, the raw material sourcing and the validation are project costs rather than volume costs.
IP, Exclusivity and the Contract You Sign First
Sign the ownership terms before the first concept document is shared, not after the formula works. The agreement should say who owns the formula, who owns improvements made during development, what exclusivity is granted and by which dimension - territory, channel or category - how long it runs, and what happens to the formula and the artwork if the relationship ends.
Two clauses are routinely missed. The first covers improvements: if your feedback produces a change that later appears in another customer's product, the agreement should already say whether that is permitted. The second covers the reverse-engineering question, because a formula you own is only valuable if the manufacturer is not free to build an equivalent for a competitor. Our MOQ and pricing negotiation guide covers how to trade volume commitments for exclusivity without overpaying for it.
Budgeting and the Timeline You Should Plan For
Plan in phases rather than around a single delivery date, because each phase carries different risk and different cost. Brief and feasibility runs one to two weeks; first prototypes two to four weeks after a signed brief; two or three iteration cycles follow; then stability and challenge testing run for weeks after the formula is frozen, and a pilot batch precedes the commercial run. Treat any single end-to-end figure as an estimate until the formula is frozen, because iteration is the variable nobody can forecast.
Budget on the same logic. Development work, laboratory testing, pilot production and packaging tooling are separate line items, and third-party testing plus any market registration are client costs rather than manufacturer costs. A project that budgets only for the formula will be surprised by the tooling; one that budgets only for tooling will be surprised by the testing. Ask for the full list at feasibility stage, in writing.
Why Custom Projects Fail
The failures are rarely chemical. They are a brief that changed after the formula was frozen, a claim discovered to be unsupportable after the artwork was printed, a pack chosen for aesthetics that the dispenser cannot handle, or an exclusivity assumption that was never written down. A project that starts with a frozen brief and a signed ownership position avoids most of them.
The remaining failures come from sequencing: stability started before the formula was frozen, tooling ordered before the pack compatibility test, or a launch date announced before the pilot batch. If you are scoping a bespoke project, send us the brief and the target markets and we will tell you which phases can run in parallel and which cannot. Our custom formula range shows what a typical development file contains.
Frequently Asked Questions
How long does custom formula development take?
Longer than a catalogue launch, and the honest answer depends on how many iteration cycles the brief needs. Brief and feasibility run one to two weeks, first prototypes two to four weeks, then iterations, then stability and challenge testing, then a pilot batch before the commercial run. Plan in months rather than weeks, and treat any single end-to-end figure as an estimate until the formula is frozen, because iteration drives the variance.
When should I choose custom over a catalogue base?
When one of three conditions is true: an ODM SKU has proven repeat purchase and differentiation is now the constraint, a retailer or distributor requires an exclusive formulation, or a market requirement cannot be met by any catalogue base. If none applies, a catalogue base gets you to market with the same quality system at a fraction of the cost, and you keep the custom option for the SKU that has earned it.
Who owns a custom formula?
It depends entirely on what the contract says, which is why the ownership clause is signed before the brief is shared. In a development-for-hire arrangement the brand typically owns the formula and pays for the development; in a shared-development arrangement the manufacturer may retain ownership and grant exclusivity by territory or channel. Either works commercially, but the treatment on termination and the rights to improvements must be explicit.
What testing does a custom formula need before launch?
At minimum accelerated and real-time stability, a preservative challenge test for any water-based system, pack compatibility testing in the final dispenser, and microbiological release specifications per batch. Leave-on and oral formats add an ingredient review against the real exposure route, and enzymatic products need retained activity measured at each timepoint. Third-party testing is a client cost and should appear in the project budget from the start.
Can a custom formula be exclusive to my brand?
Yes, and exclusivity is normally granted by dimension rather than universally: a territory, a channel, a category or a named retailer. Be specific, because an exclusivity clause that says only exclusive is difficult to enforce and easy to argue about. Expect to trade something for it - a volume commitment, a development fee or a longer term. Our MOQ and pricing guide covers how that trade is usually structured.
What is the minimum order for a custom formula?
Our standard ODM minimum is 1,000 pieces per SKU for catalogue bases. A bespoke formula is quoted per project rather than against a standard minimum, because the pilot batch, the raw material sourcing and the validation are project costs that exist whatever the fill volume is. Ask for the development cost and the production minimum to be quoted separately, so you can see which part of the investment is one-off.
Conclusion
Custom development rewards brands that know exactly what they are differentiating and are willing to wait for validated data. The four phases are not bureaucracy; each one exists to stop a specific, expensive mistake from reaching a commercial batch. Freeze the brief, sign the ownership terms early, and let stability and the pilot batch set the launch date rather than the other way round. Budget the tooling and the testing as separate lines, because the two most common overruns are the ones nobody quoted in the first place. Done that way, a bespoke formula becomes an asset you can defend. Done the other way, it becomes a development invoice with a product attached.
Explore our Custom Formula Development for samples and documentation.
