June 1, 2026 is the date the second wave of containerboard price increases actually took effect in North America. About six to seven months after the first-wave hike in the second half of 2025, the five major mills moved together with $50 to $70 per ton increases. Because the hike size and timing were nearly synchronized, this wave is likely to feed into Korean import prices much faster than the first one did.

This post does not stop at announcing that a hike happened. It organizes how Korean export packaging companies should simulate import prices and quote policy from June through September, now that the second wave is effective as of June 1. For a general review of the Korean corrugated and box price domino itself, also see “2026 Korea Corrugated Price Domino Recap”.

Structure of the Second-Wave Hike Effective June 1

The key numbers for this second wave are as follows.

  • Smurfit Westrock: $50 per ton increase, effective 2026-06-01
  • International Paper (IP): $70 per ton increase, effective 2026-06-01
  • Packaging Corporation of America (PCA): $50 per ton increase, effective 2026-06-01
  • Georgia-Pacific (GP): $50 per ton increase, effective 2026-06-01
  • Pratt Industries: $50 per ton increase, effective 2026-06-01

Five producers picked the same effective date and moved in a single bundle on the hike size. The usual pattern is for one mill to float an increase selectively and for the rest to fall in line two to four weeks later. This June 1 hike was announced together from early to mid-May and went into effect within a month. From the buyer side, there is less room to negotiate than during the first wave.

The drivers are not a single factor. (1) On the demand side, e-commerce, food, and industrial box demand have moved into a recovery zone. (2) On the supply side, capacity-reduction signals such as the SSK Birmingham mill review have appeared. (3) On the input side, OCC (recovered fiber) prices have climbed alongside labor and logistics costs. When all three move at once, hike announcements convert into realized prices faster.

Comparison of the June 1, 2026 containerboard hike sizes and effective dates across the five North American mills

Three Scenarios Korean Export Packaging Companies May Face in July-September

How the second wave flows through to Korean import prices for containerboard and boxes is not a single outcome. Here are the three scenarios most likely to land on Korean export packaging companies during June-September.

Scenario A: Full Pass-Through (Probability: Medium-High)

If all five producers’ increases hold, Korean import quotes are likely to carry an additional $40 to $60 per ton hike notice starting from late June through early July. This is the pattern observed in the first wave.

  • Late June to early July: Distributors send revised quotes (existing contracts usually stand)
  • Mid-July: Hike applied from July shipments onward
  • August-September: Spreads widen by containerboard grade (linerboard, fluting, KraftLiner)

Scenario B: Partial Pass-Through (Probability: Medium)

If one or two of the five negotiate a smaller hike on selected categories, Korean import prices may absorb only 60 to 80 percent of the announced increase. In that case, the price gap with Southeast Asian and European containerboard narrows, and sourcing diversification becomes a real option.

  • Checkpoint: Timing of official US transaction-price releases through mid-July
  • Alternative review: Compare with Indonesian, Thai, and Finnish KraftLiner offers

Scenario C: Delayed Effect or Re-Announce (Probability: Low)

If demand softens again or OCC prices fall back, the effective hike could slide past August. Some Korean importers may temporarily hold June-July quotes in that case.

  • Signal: June-July US transaction-price indicators (e.g., Pulp & Paper Week, RISI) absorb only part of the hike
  • Response: Roll quote expirations every two weeks; treat long-term contracts cautiously

What Korean Export Packaging Companies Should Actually Do in June-September

Three-month containerboard import-price simulation sheet and quote policy notes for Korean export packaging companies

For Korean export packaging companies, this second wave is not about following prices passively. It is the moment to review the three-month simulation sheet and the quote policy together.

1. Three-Month Containerboard Import-Price Simulation Sheet

Build a June / July / August / September x KraftLiner / TestLiner / Fluting / White-Top matrix and write three lines in each cell.

  • Current quote price (USD/ton)
  • Post-hike price under Scenario A
  • KRW per ton under FX assumptions (USD/KRW at 1,360 / 1,380 / 1,400)

This sheet is what sales, procurement, and production should all look at when making quote, delivery, and inventory decisions. No single department should be reading it alone.

2. Separate Policy for August Quotes and September Deliveries

The impact of this wave will land hardest on August quotes for September delivery. Sales teams should split the response into two tracks.

  • August quotes: Reflect the hike with a short 14-21 day validity window
  • September deliveries: Hold current pricing only on POs placed by end of July (with available volume explicitly capped)

Even this single separation reduces buyer pushback like “why did the quote on the same SKU change?”

3. Catalog Substitute Grades and Origins in Advance

Among SKUs that mainly use US KraftLiner, identify the items that can shift to Southeast Asian KraftLiner or domestic Korean TestLiner. The longer the hike pass-through takes, the more valuable that alternative list becomes. Fill in the following table ahead of time.

  • Own SKU code / box grade (SW/DW)
  • Current US grade in use / basis weight
  • Possible substitutes (Southeast Asian KraftLiner, Korean TestLiner, Finnish KraftLiner, etc.)
  • Whether ECT/BCT testing is required after substitution (see “ECT/BCT/McKee Recap”)

4. Standardized Talk-Tracks for Buyers

When a US buyer asks “what does the June 1 price increase mean for our next PO?”, the sales team needs a one-line answer. Not “it’s been announced and we’re discussing it,” but “hike size / effective date / our response” in one sentence.

  • Korea HQ line: “IP at $70, SW, PCA, GP, and Pratt at $50 effective June 1; our pass-through begins gradually from July shipments.”
  • Korea HQ line: “We are reviewing alternative origins for selected KraftLiner grades and will present options starting with the August quote.”

Versus the First Wave: What Has Changed

Compared with the first wave in the second half of 2025, this June 1 effect differs in four ways.

  • Speed: First wave took six to ten weeks from announcement to effect. This time it compressed to about four weeks.
  • Synchronization: First wave was led by three mills. This time all five major mills moved together.
  • Supply signal: First wave had almost no capacity signal. This time it comes with capacity-reduction signals such as the SSK Birmingham review (see “Smurfit Westrock LSE Delisting and UK Mill Closure”).
  • OCC trend: Recovered-fiber prices turned firmer again in late May.

Adding those four together, the more sensible read is that this second wave is a moment to rewrite quote policy by watching capacity, OCC, and FX together through June-September, not just to track the headline price.

Conclusion

The second-wave North American containerboard hike effective June 1, 2026 is not an event Korean export packaging companies can close out as “prices went up again.” Five mills synchronized, capacity-reduction signals appeared, and OCC turned firmer all at once. As a result, July, August, and September quotes are likely to be affected in stages.

What needs to happen now is to (1) build the three-month containerboard import-price simulation sheet, (2) separate the August quotes from September deliveries and standardize the sales talk-tracks, and (3) catalog substitute grades and origins. The next review should be updated at the late-July release of US transaction-price indicators.

About the Author

PackingMaster: Editor of PaperPackLog. Curates and organizes market trends, product information, and technical insights for the paper-packaging industry.

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