US containerboard rises another $50/st in June, with Smurfit Westrock the most direct beneficiary

Overview

This report is Goldman Sachs' event commentary on US paper prices, focusing on the US containerboard and paperboard price data released by RISI on June 19. The report notes that containerboard rose $50/st month over month in June, for a cumulative year-to-date increase of $100/st, with price momentum stronger than previously expected by the market; however, paperboard prices remained flat, indicating divergence in supply-demand tightness across different paper grades.

Core views

Goldman Sachs' core view is: first, the containerboard price increase is not just short-term forward buying, as rising costs and supply contraction are beginning to take effect; second, in markets where supply is more constrained, even limited demand changes can trigger steeper price increases; third, it will still take time for price increases to pass through to corrugated boxes, because RISI still reports weak box demand; fourth, Smurfit Westrock, with the highest exposure to North America and containerboard/boxes, is the biggest beneficiary within coverage, and Goldman Sachs maintains its Buy rating.

Analysis framework

The report combines the RISI price index, raw material and transportation costs, capacity closures, order backlogs, mill inventories, downstream demand, and company EBITDA exposure to assess the sustainability of this round of containerboard price increases and their impact on Smurfit Westrock's earnings; for valuation, it uses a 2026/27 EV/DACF multiple framework.

Methodology notes

• Industry supply-demand analysisRISI price index and supply-demand validation

  Use monthly paper prices, capacity closures, order backlogs, and inventories to judge the quality of containerboard price increases.

  The report cites the RISI index to confirm the June containerboard price increase and combines it with about 10% capacity closures, 5-8 weeks of order backlogs, and low inventories to show tightening supply and demand.

• Company exposure analysisEBITDA regional and product exposure mapping

  Use the share of North American EBITDA and the share of containerboard/box business to measure a company's sensitivity to industry price changes.

  Goldman Sachs estimates that about 60% of Smurfit Westrock's EBITDA comes from North America, of which about 70% is exposed to containerboard/boxes, making its earnings more sensitive to US containerboard price increases.

• Valuation methodologyEV/DACF multiple valuation

  Use 2026/27 EV/DACF multiples to determine the target price.

  Goldman Sachs uses a 9.5x 2026/27 EV/DACF valuation, derived by multiplying the 9.1x through-cycle historical EV/DACF by a factor of 1.04, because forecast CROCI is above historical levels.

• Equity factor frameworkGS Factor Profile

  Compare individual stocks with the market and peers across growth, financial returns, valuation multiples, and composite factors.

  The appendix explains that the Goldman Sachs Factor Profile uses indicators such as forward sales, EBITDA, EPS, ROE, ROCE, CROCI, and valuation multiples to form percentile rankings.

Asset mapping & comparison

Structured mapping from thesis to named assets (strengths, weaknesses, peers, risks).

• Smurfit Westrock (SW)

  Core beneficiary and covered company

  Strengths

  About 60% of EBITDA comes from North America, and about 70% of North American business is exposed to containerboard/boxes, directly benefiting from US containerboard price increases; Goldman Sachs maintains a Buy rating.

  Weaknesses

  It will still take time for paper price increases to pass through to corrugated boxes, and there are still execution pressures around integration of legacy North American businesses, contract exits, and asset upgrades.

  Comparison

  Compared with covered companies such as Mondi, SCA, SIG Group, Stora Enso, and UPM-Kymmene, SW has the highest exposure to the North American market and containerboard prices.

  Risks

  Packaging demand below expectations, incomplete realization of price increases, higher-than-expected capital expenditures, or value-dilutive acquisitions could all weaken the investment thesis.

• US containerboard/corrugated packaging chain

  Core industry price variable

  Strengths

  The June containerboard price increase was confirmed by RISI, while longer order backlogs, low inventories, and capacity closures jointly support short-term price momentum.

  Weaknesses

  Demand improvement may partly reflect forward buying, and there is still a lag before paper price increases pass through to corrugated boxes.

  Comparison

  Compared with paperboard, containerboard currently has tighter supply and demand and clearer price increases.

  Risks

  If demand falls back, buyers resist, or cost pressures ease, further seller attempts to raise prices may fail.

• SBS/CRB paperboard

  Lagging observation variable

  Strengths

  SBS prices are close to CRB, which may drive future improvement in SBS demand and tighten the market.

  Weaknesses

  Paperboard prices in June were still flat month over month, and buyers have not yet felt the same degree of tightness as in containerboard.

  Comparison

  Price momentum is clearly weaker than containerboard, which is the main manifestation of divergence in this round of paper industry price increases.

  Risks

  If seller price increases in June/July fail to materialize, it will weaken the broader paper sector price increase narrative.

Key data

• June containerboard price change+$50/stConfirmed by the RISI index as a month-over-month increase in June.
• Year-to-date containerboard increase+$100/stThe report believes the price increase reflects rising costs and supply contraction.
• Capacity closuresapproximately 10%The report says about 10% of containerboard capacity has been closed since early 2025, resulting in tighter supply.
• Order backlog5-8 weeksAbove about 5 weeks in May, indicating sellers still see market strength.
• June paperboard priceflat month over monthBuyers believe the paperboard market is less tight than containerboard.
• Smurfit Westrock North America EBITDA shareapproximately 60%The report says SW has the highest North American exposure within coverage.
• Containerboard/box exposure within North American EBITDAapproximately 70%Goldman Sachs estimates this exposure makes SW the biggest beneficiary of US containerboard price increases.
• Rating and target priceBuy / $4912-month target price; disclosed price of $44.20, corresponding to approximately 10.9% upside.

Impact & implications

In the short term, US containerboard price increases are a positive catalyst for Smurfit Westrock, and Goldman Sachs expects the market reaction on the day to be broadly positive; in the medium term, if the price increases can pass through to corrugated boxes and receive demand validation during the September-November North American box peak season, SW earnings expectations could be supported. However, if current demand partly reflects forward buying, paperboard price increases continue to fail, or packaging demand weakens, the sustainability of this round of price increases may still be questioned.

Risks

• US tariffs may fail to deliver the margin improvement expected by Goldman Sachs, putting pressure on paper price and earnings forecasts.
• Packaging demand may be weaker than expected, especially if consumer confidence is affected by global uncertainty or conflict in the Middle East.
• Current demand may include forward buying, and if subsequent real demand is insufficient, containerboard price increases may be difficult to sustain.
• If volume revisions are higher than expected as Smurfit Westrock exits loss-making facilities and box contracts in North America, this will pose downside risk to earnings.
• Capital expenditures required to improve the profitability of Westrock's US assets may be higher than expected.
• Value-dilutive acquisitions may weaken shareholder returns and the investment thesis.
• Poor pass-through of paperboard and corrugated box price increases may prevent upstream paper price improvement from being fully converted into company profits.

What to watch

• Whether subsequent monthly RISI containerboard prices continue to rise or remain elevated.
• Whether sellers attempt further price increases in the coming months, and how willing buyers are to accept them.
• Whether corrugated box demand and prices follow containerboard higher, especially during the September-November North American box demand peak season.
• Whether order backlogs remain at 5-8 weeks or lengthen further, and whether mill inventories stay low.
• Whether the price relationship among paperboard, SBS, and CRB leads to improved SBS demand.
• Progress on Smurfit Westrock's North American integration, exit from loss-making contracts, and capacity rationalization.
• The company's 2026 capital expenditure guidance, margin improvement, and M&A discipline.