The US Polystyrene market is set to face consecutive bearish trend in the coming November and December 2025, after declining for two straight months in September and October. The market is under relentless pressure from high stocks, seasonal demand slowdowns and decreasing feedstock costs, and further monthly decreases of 1.4% are forecast for the rest of the year, with prices down about 3-4% in September and 4% in early October.
The US Polystyrene market is under increasing pressure at the end of 2025. September and October have already brought two price decreases in a row, and the price trend for November and December seems to be going the same way. Market analysts say what began as a modest weakness has turned into a persistent downtrend in its twelfth week.
Polystyrene prices dropped by around 3-4% in September month over month. The drop was inconsistent--early September was flat, then a 1% drop appeared mid-month. The third week saw a larger 3% decrease, then a slight decrease to end the month of September. Excess supply of styrene feedstock was a factor, as were economic fears that caused buyers to be more selective over their purchases.
Polystyrene production activity was steady over the two months: producers seemed to be holding back at a moderate production level in spite of the price situation. Strong domestic feedstock availability, along with ongoing Asian imports, created margin pressure that let inventories run freely. The large inventories continued to hold down the competitiveness of exports and also restrained upward price movement.
The demand situation for Polystyrene was relatively mixed among major end users. The packaging sector remained surprisingly strong in September, that Packaging Corporation of America had net sales of approximately $2.3 billion for the third quarter, a slight increase from $2.2 billion in 2024, with net income increasing to approximately $226.9 million. But extended studies suggested mild contraction amid uncertainty around tariffs and economic situation.
Electronics fabrication was a relative bright spot for Polystyrene usage, especially in high impact protective packaging. Canon Electronics net sales rose 6% for nine months to September, driven by demand in imaging and semiconductor equipment. However, this segment’s outperformance was not enough to compensate for the overall resin market weakness related to the feedstock oversupply and subdued Polystyrene purchasing.
Looking for November and December, market analysts estimate that the Polystyrene prices will continue to deteriorate by about 1.4% for each month. With winter coming, they anticipate a drastic reduction in construction activity, and a drop in demand for expanded Polystyrene insulation products.
Polystyrene faces a complex demand picture in the holiday season as conservative buying ahead of the end of the year may dampen price stabilization. Furthermore, producers should be able to retain margins in the face of slumping raw material prices because of year-end weakness in crude oil markets, while holiday-related industrial production slowdowns are expected to further reduce plant utilization rates and increase Polystyrene inventory, potentially pointing the bearish price picture through year-end.
