Phosphate Procurement
DAP vs MAP Phosphate Fertilizers: Procurement Guide for Industrial Buyers
Why Phosphate Selection Matters at Scale
For industrial fertilizer buyers, cooperatives, and national distributors procuring phosphate in container loads or vessel shipments, the choice between Diammonium Phosphate (DAP 18-46-0) and Monoammonium Phosphate (MAP 11-52-0) directly impacts crop performance in your end-customer base, procurement cost per unit of phosphorus delivered, and the agronomic suitability of your product for the soils in your market. This guide explains the key differences and provides a framework for making the correct specification decision for your procurement program.
Complete Specification Comparison
| Parameter | DAP (18-46-0) | MAP (11-52-0) |
|---|---|---|
| Total Nitrogen (N) | 18% minimum | 11% minimum |
| Available P₂O₅ | 46% minimum | 52% minimum |
| Water-soluble P₂O₅ | 39% minimum | 48% minimum |
| Total nutrients | 64% minimum | 63% minimum |
| Soil pH reaction | Mildly alkaline (pH 7.5–8.0 in solution) | Mildly acidic (pH 4.0–4.5 in solution) |
| Granule appearance | Brown / dark grey granules | Light grey / off-white granules |
| Water solubility | Good | Excellent |
| Drip/fertigation suitability | Limited (granular standard grade) | Excellent (water-soluble grade available) |
| Typical price relationship | Lower cost per MT | Slightly higher per MT; higher P₂O₅ content |
| HS Code | 3105.30 | 3105.40 |
Soil Type: The Primary Decision Factor
The single most important factor in choosing between DAP and MAP is the typical soil pH of the agricultural region you serve. This drives the soil reaction and phosphorus availability after application:
- Acidic soils (pH below 6.5) — common in humid tropical regions (Southeast Asia, West Africa, Latin America). DAP is preferred here. Its mildly alkaline soil reaction partially corrects soil acidity, and phosphorus availability is good in the 6.0–7.0 pH range where DAP performs best.
- Alkaline or calcareous soils (pH above 7.0) — common in drier regions (Middle East, North Africa, parts of South Asia, northern cereal belts). MAP is preferred. Its mildly acidic soil reaction helps to bring localized pH into the optimal phosphorus availability zone and its higher water-soluble P₂O₅ content (48%) ensures faster uptake in soils where fixation is high.
Application Timing: Basal vs. Starter
Both DAP and MAP are primarily basal fertilizers — applied at or before planting. However, MAP has a lower salt index than DAP, making it safer for seed-zone placement where germinating seedlings may come into contact with fertilizer granules. This makes MAP the preferred specification for starter fertilizer programs and any procurement where the product will be used in-furrow or as a seed-placement fertilizer.
For large-scale basal broadcasting applications — rice paddies, sugarcane fields, maize, and general cereal production — DAP typically delivers equivalent agronomic results at lower cost per MT, making it the dominant choice for high-volume commodity agriculture procurement.
Bulk Blending Compatibility
Both DAP and MAP are compatible with granular urea and MOP for NPK bulk blending operations. Granule size compatibility is critical — both are available in the 2.0–4.75 mm range that matches standard granular urea and MOP specifications. MAP's excellent water solubility also makes it the preferred phosphate feedstock for water-soluble NPK formulas used in drip irrigation and greenhouse production.
Procurement Checklist for Phosphate Buyers
- Confirm target soil type and pH for your end-user market — this determines DAP vs MAP
- Specify granule size requirement (2.0–4.75 mm standard; water-soluble powder if fertigation)
- Request COA from the last three shipments — check P₂O₅, N, moisture, and granulometry
- Specify SGS or Intertek pre-shipment inspection for first-time sourcing
- Confirm HS code for import — 3105.30 (DAP) or 3105.40 (MAP) for customs planning
- Verify source country — Morocco, Saudi Arabia, and China are primary origins for DAP; China and Morocco for MAP
- Confirm anti-dumping or import duty status for your destination country
- Negotiate CIF delivery for first orders to control freight risk
Price Per Unit of Phosphorus: DAP vs MAP
When evaluating which grade delivers better value, calculate the cost per unit of P₂O₅ delivered, not the cost per MT of product. MAP contains 52% P₂O₅ vs DAP's 46% — so for the same investment in product cost, MAP delivers more phosphorus per MT. In markets where soil conditions make both grades equally agronomically suitable, this calculation often favors MAP despite its higher gross price per MT.
How MC INTERNATIONAL S.P.A Supports Phosphate Buyers
MC INTERNATIONAL S.P.A CO., LTD is both a DAP fertilizer supplier and MAP fertilizer supplier serving distributors and industrial buyers across Asia, Africa, and the Middle East. We source both grades from audited top-tier producers and maintain consistent supply under ISO 9001:2015 quality controls. COA, SGS/Intertek inspection, and full export documentation are standard with every shipment.
For buyers who require both grades — for example, a national distributor serving mixed soil zones — we can supply DAP and MAP in a single consolidated shipment to reduce freight cost and simplify procurement logistics.