Pillar Two is usually discussed as a compliance issue.

That is understandable.

Groups are focused on registration, data gathering, software, GloBE Information Returns, Overseas Return Notifications, UK top-up tax returns and safe harbour analysis.

But that is only one side of the story.

For acquisitive groups, private equity investors, family offices and internationally active businesses, Pillar Two is now also a deal issue.

It affects due diligence.

It affects pricing.

It affects tax warranties.

It affects indemnities.

It affects completion accounts.

It affects post-acquisition integration.

And, in some cases, it may affect whether a target is as tax-efficient as the buyer thinks it is.

The point is simple.

A business can look attractive on an EBITDA basis, but still bring with it Pillar Two complexity that has not been priced into the transaction.

That complexity may not appear clearly in the target’s corporation tax returns.

It may not be visible from the statutory accounts alone.

It may not be obvious from a standard tax due diligence report.

But it may still become the buyer’s problem after completion.

The question is no longer only “what tax does the target pay?”

Traditional tax due diligence asks familiar questions.

Has the target filed its tax returns?

Are there open enquiries?

Are there uncertain tax positions?

Are there transfer pricing exposures?

Are there withholding tax issues?

Are there VAT risks?

Are tax losses available?

Are there employment tax exposures?

Those questions remain important.

But Pillar Two adds a different question:

What happens to this target inside the buyer’s global Pillar Two profile?

That is a much more sophisticated question.

A target that is outside the scope of Pillar Two on a standalone basis may become relevant once acquired by a larger group.

A target that has never prepared Pillar Two data may suddenly need to provide it.

A target operating in a low-tax jurisdiction may create additional top-up tax exposure for the buyer.

A target relying on tax incentives may produce a worse Pillar Two outcome than its local tax position suggests.

A target with weak financial reporting systems may create a compliance burden that was not identified during diligence.

A target with transfer pricing adjustments, hybrid instruments, local tax holidays or deferred tax assets may require far more analysis than the headline tax rate indicates.

This is where standard due diligence can miss the point.

Pillar Two does not simply ask whether the target complied with local tax law.

It asks how the target’s numbers behave when inserted into a global minimum tax framework.

A low tax rate is no longer automatically a value driver

For many years, a low effective tax rate could increase perceived value.

A business with strong margins and low cash tax could look particularly attractive.

That analysis now needs more care.

Under Pillar Two, a low local tax rate may not be a permanent advantage if the group is within scope and the relevant jurisdiction does not produce a qualifying effective tax rate.

The buyer may still benefit from local tax incentives for local tax purposes.

But the economic benefit may be reduced if top-up tax is payable elsewhere in the group.

This does not mean that low-tax jurisdictions are automatically unattractive.

That would be too simplistic.

It means the buyer needs to understand whether the local tax advantage survives the Pillar Two analysis.

That is a very different valuation question.

It is also a question that needs to be answered before signing, not after completion.

Tax incentives need a Pillar Two review

This is particularly important where the target benefits from tax holidays, super-deductions, patent box regimes, investment incentives, special economic zone regimes, notional interest deductions or other preferential local tax arrangements.

Historically, the due diligence focus would often be:

Is the incentive valid?

Has the company met the conditions?

Can the incentive be challenged?

How long does it last?

Can it be transferred after acquisition?

Those questions are still relevant.

But they are incomplete.

The further question is whether the incentive produces a Pillar Two top-up tax issue.

A tax relief that is valuable for local corporation tax purposes may be less valuable at group level if it depresses the jurisdictional effective tax rate below the required minimum.

In a transaction context, that matters.

If the buyer has priced the target assuming that the tax incentive will preserve cash tax savings, but Pillar Two later absorbs part of that benefit, the buyer may have overpaid.

This is not a theoretical issue.

It is a valuation issue.

The buyer may inherit a data problem

Pillar Two is not only about tax cost.

It is also about data.

A target may have perfectly acceptable local accounts and tax returns, but still be poorly prepared for Pillar Two reporting.

The buyer may need information by jurisdiction, entity, permanent establishment, covered tax category, deferred tax category, accounting standard, CbCR data source and consolidation adjustment.

The target may never have collected that data in a way that can be used for Pillar Two.

That creates a post-completion problem.

The buyer may discover that the target cannot provide reliable historical data, cannot reconcile local accounts to consolidation packages, cannot explain deferred tax balances, or cannot identify relevant adjustments with sufficient precision.

In a deal timetable, that may look like an administrative issue.

In practice, it can become a material integration cost.

It can also create uncertainty in the buyer’s first post-acquisition Pillar Two filing cycle.

That is why Pillar Two diligence should not only ask whether there is top-up tax.

It should ask whether the buyer can obtain the data required to calculate and evidence the position.

The SPA needs to catch up

Many sale and purchase agreements still treat tax risk in a pre-Pillar Two way.

They contain warranties on tax compliance, payment of tax, tax residence, transfer pricing, withholding tax, VAT, payroll taxes and tax disputes.

Those provisions are useful.

But they may not be enough.

Pillar Two creates exposures that do not always fit comfortably into traditional tax warranty language.

For example, what if the target has not maintained the information required for the buyer’s Pillar Two reporting?

What if pre-completion arrangements create post-completion top-up tax exposure?

What if the seller has relied on a tax incentive that is valid locally but materially affects the buyer’s group effective tax rate?

What if a pre-completion transfer pricing adjustment changes the buyer’s safe harbour analysis?

What if a deferred tax asset recognised before completion does not produce the expected Pillar Two outcome?

What if the target has provided CbCR data that cannot be reconciled to the accounts?

These are not always standard corporation tax liabilities in the traditional sense.

But they can still affect the buyer economically.

The SPA should therefore be reviewed through a Pillar Two lens.

That may require specific warranties, information covenants, cooperation obligations and, in appropriate cases, bespoke indemnity protection.

Locked box and completion accounts require particular care

Pillar Two also raises practical issues for locked box and completion accounts mechanisms.

In a locked box deal, the buyer is economically exposed from the locked box date.

If Pillar Two tax attributes, accounting adjustments or jurisdictional tax positions change between the locked box date and completion, the buyer needs to understand how that risk is allocated.

In a completion accounts deal, the question is whether any Pillar Two-related liabilities, provisions, deferred tax effects or tax reimbursements are captured in the price adjustment mechanism.

The drafting needs to be clear.

A dispute after completion about whether Pillar Two top-up tax is a pre-completion tax, a post-completion tax, a group tax, an excluded tax, a covered tax or a buyer-side tax is exactly the kind of dispute that should be avoided at drafting stage.

The issue is not simply technical.

It is commercial.

Who bears the economic cost?

Who controls the filing?

Who has the data?

Who signs the return?

Who manages the enquiry?

Who receives the benefit of any adjustment?

Those questions should not be left to implication.

Private equity needs a portfolio-level view

Private equity investors should be particularly careful.

A portfolio company may not be within scope on a standalone basis.

But the wider fund structure, aggregator entities, co-investment arrangements and portfolio composition may require careful analysis.

In addition, buy-and-build strategies can move quickly.

A group that is outside the Pillar Two perimeter at acquisition may become relevant later as the platform expands.

That means Pillar Two should not be reviewed only at exit.

It should be considered at acquisition, during bolt-on transactions, during refinancing and before any material restructuring.

For private equity, the risk is not only current tax leakage.

It is also exit readiness.

A future buyer may ask harder Pillar Two questions than the current seller has answered.

If the portfolio company has not maintained the right evidence, the issue may affect value, timing or negotiation leverage on exit.

The practical diligence questions

In a transaction, buyers should now ask a focused set of Pillar Two questions.

Is the target already part of an in-scope group?

Would the target become part of an in-scope group after acquisition?

Which jurisdictions drive the Pillar Two profile?

Does the target benefit from low-tax regimes, tax holidays or preferential tax incentives?

Are there material deferred tax balances?

Are there transfer pricing adjustments that affect jurisdictional profit?

Are there hybrid entities, hybrid instruments or mismatch outcomes?

Is the CbCR data reliable and reconcilable?

Can the target provide the data needed for the buyer’s Pillar Two calculations?

Are there local tax attributes whose value may be reduced under Pillar Two?

Does the SPA allocate Pillar Two risk clearly?

Are post-completion cooperation obligations strong enough?

Would the buyer be comfortable defending the position to HMRC or another tax authority?

These questions should be asked early.

Not at the end of the deal.

Not after signing.

Not when the first Pillar Two filing deadline arrives.

The commercial point

Pillar Two does not make every transaction more expensive.

It does not automatically create top-up tax.

It does not mean that every low-tax structure is defective.

But it does mean that internationally active buyers need a more disciplined approach.

The tax profile of a target can no longer be assessed only by looking at local tax compliance and headline effective tax rates.

The buyer needs to understand the target’s position inside the global group architecture.

That is the real change.

A target may be compliant locally but still problematic under Pillar Two.

A tax incentive may be valid locally but less valuable economically.

A low tax rate may be attractive commercially but neutralised at group level.

A clean tax return may sit alongside weak Pillar Two data.

A standard SPA may fail to allocate the risk properly.

That is why Pillar Two now belongs in M&A diligence.

It belongs in the tax structuring paper.

It belongs in the valuation discussion.

It belongs in the SPA negotiation.

It belongs in the post-completion integration plan.

The conclusion

The first wave of Pillar Two work has focused on compliance.

That was necessary.

The next wave will focus on transactions.

Buyers will need to know what they are acquiring.

Sellers will need to prepare for harder tax due diligence.

Private equity investors will need to consider the impact across the investment lifecycle.

Boards will need to understand whether the group is acquiring not only a business, but also a Pillar Two data problem, tax cost problem or governance problem.

The practical message is clear.

Do not wait until after completion to ask Pillar Two questions.

By then, the price has been agreed, the warranties have been signed, the data problem has been inherited and the commercial leverage may have gone.

Pillar Two is no longer only a compliance deadline.

It is now a deal risk.

And deal risks need to be identified before the deal is signed.

Vectigalis Tax advises internationally active groups, entrepreneurs, family offices, private equity-backed businesses and finance teams on UK and international tax structuring, Pillar Two readiness, transfer pricing, cross-border M&A tax risk and tax governance.

Our approach is practical and technically robust: identify the exposure, assess the commercial impact, protect the client’s position and build an HMRC-defendable action plan before the issue becomes a dispute.

Mail: info@vectigalistax.co.uk

Website: www.vectigalistax.co.uk